bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduction of Gamanthera to Licaria (Lauraceae)
Authors: Kostermans Andre J. G. H.
Published: April 2006

Kostermans, A. J. G. H.: Reduction of Gamanthera to Licaria (Lauraceae). – Taxon 42: 853‐854. 1993. – ISSN 0040‐0262.

The monotypic genus Gamanthera, recently described, was based mainly on the characteristic of the fused stamens of the third, inner whorl. However, in Licaria the stamens of the third whorl are either entirely free, or partly connate or united into a staminal tube. The depicted flower of Gamanthera has a gynoecium outside the staminal whorls, but this is considered an abnormality. Gamanthera is therefore reduced to synonymy under Licaria and the necessary new combination is made.
(1074‐1082) Nine proposals to conserve generic names of lichenized fungi
Authors: Jørgensen Per M. , Santesson Rolf
Published: April 2006

Jørgensen, P. M. & Santesson, R.: (1074‐1082) Nine proposals to conserve generic names of lichenized fungi. – Taxon 42: 881‐887. 1993. – ISSN 0040‐0262.

Conservation proposals are made for Arthrorhaphis, Calinaria, Haematomma, Icmadophila, Laurera, Polysporina, Sarcogyne, Scutula and Umbilicaria.
Juniperus monticola (Cupressaceae) revisited
Authors: Adams Robert P. , Zanoni Thomas A.
Published: April 2006

Adams, R. P. & Zanoni, T. A.: Juniperus monticola (Cupressaceae) revisited. Taxon 42: 85‐86. 1993. ISSN 0040‐0262.

A reexamination of the nomenclature indicates that Juniperus monticola Martínez is the correct name for the Mexican alpine species and not Juniperus sabinoides (Kunth) Nees.
The nomenclature of Erodium saxatile Pau and Erodium celtibericum Pau (Geraniaceae)
Authors: Crespo Manuel B. , Mateo Gonzalo
Published: April 2006

Crespo, M. B. & Mateo, G.: The nomenclature of Erodium saxatile Pau and Erodium celtibericum Pau (Geraniaceae). ‐ Taxon 42: 96‐100. 1993. ‐ ISSN 0040‐0262.

Historical and nomenclatural features are reported for two endemics from eastern Spain the names of which have been recently discussed. Erodium saxatile Pau [including E. valentinum (Lange) Greuter & Burdet] is revived for a taxon from Alicante Province, which was called Geranium saxatile but was never described by Cavanilles. E. celtibericum Pau is maintained for a taxon from Castellón Province, which was described but never named by Cavanilles. Both names are typified and their synonymies annotated.
Withdrawal of proposals for conservation of family names of algae
Authors: Silva Paul C.
Published: April 2006

Silva, P. C.: Withdrawal of proposals for conservation of family names of algae. ‐ Taxon 42: 121‐122. 1993. ‐ ISSN 0040‐0262.

Seven conservation proposals are withdrawn.
EARLY COLLECTORS OF PLANTS FROM HONDURAS AND THE CONFUSION WITH BRITISH HONDURAS (BELIZE)
Authors: Nelson Cirilo
Published: April 2006

An historical account is given of plant collectors in Honduras before 1945, the year when J. Lanjouw published a short list of plant collectors for Honduras with some confusion between Honduras and British Honduras. In particular, he noted R. Temple as a collector from the Republic of Honduras and not from the British colony, now Belize.
BEYOND HYPERTAXONOMY
Authors: Frey R.
Published: April 2006

The paper of Skov (1989) has provoked additional comments from an everyday Macintosh user, which hopefully will help future “Hypertaxonomists” find fully adequate solutions to their needs.

The use of HyperCard as a database program for taxonomic data presents one with the problems of a relatively slow program that has a limited capacity for data exchange. This should be evaluated before working with large amounts of data using this program. A combination of dBaseMac and HyperCard is recommended as a push‐button solution as easy to use as HyperTaxonomy by Skov (1989).
Epitypification of Vitellaria paradoxa C. F. Gaertn. (Sapotaceae)
Authors: Hall John B. , Hindle Julia R.
Published: April 2006

Hall, J. B. & Hindle, J. R.: Epitypification of Vitellaria paradoxa C. F. Gaertn. (Sapotaceae). – Taxon 44: 409‐410. 1995. – ISSN 0040‐0262.

Designating an epitype for Vitellaria paradoxa solves the problem of application of names at subspecific level imposed by the holotype consisting solely of a seed.
Databasing diversity – a distributed, public‐domain approach
Authors: Green David G.
Published: April 2006

Green, D. G.: Databasing diversity – a distributed, public‐domain approach. – Taxon 43: 51‐62. 1994. – ISSN 0040‐0262.

Distributed, public domain databases (DPDD) offer solutions to many of the problems that hinder compilation of information on biodiversity. Existing DPDD projects on Internet, especially in molecular biology, provide relevant paradigms. The software tools necessary for world‐wide retrieval of associated text and images are all freely available on Internet. Essential features of DPDDs include universal access, decentralized maintenance of component data sets, and the use of standard, tagged formats for entries. Desirable validation protocols include cross‐checks for consistency, use of quality control tags and tracing data lineage back to specimens. These issues highlight a need for new conventions on nomenclature and for registering field keys and other secondary taxonomic indexes.
Typification of the names of two species of the Cardamine pratensis group (Brassicaceae)
Authors: Marhold K. , Rayner T. G. J.
Published: April 2006

Marhold, K. & Rayner, T. G. J.: Typification of the names of two species of the Cardamine pratensis group (Brassicaceae). – Taxon 43: 77‐83. 1994. – ISSN 0040‐0262.

Cardamine rivularis Schur is lectotypified by a specimen at Vienna (W) collected by Schur in Romania. C. matthioli Moretti is lectotypified (or neotypified) by a specimen at Florence (FI) collected by Moretti in Lombardy. The confusion concerning the latter's author and place of publication is resolved: bibliographical details and chronology of 5 publications in which the name appears, all of 1847, are discussed, showing that it was validly published on 18 Aug 1847 by Moretti.
Glaphyrosphaera, a new synonym of Wilsonisphaera (Dinophyceae, Gonyaulacales)
Authors: Schiøler Poul , Wilson Graeme J.
Published: April 2006

Schiøler, P. & Wilson, G. J.: Glaphyrosphaera, a new synonym of Wilsonisphaera (Dinophyceae, Gonyaulacales). – Taxon 44: 511‐512. 1995. – ISSN 0040‐0262.

Glaphyrosphaera Schiøler & G. J. Wilson 1994 and G. glabra Schiøler & G. J. Wilson 1994 are considered junior synonyms of, respectively, Wilsonisphaera Slimani 1994 and W. petila (Corradini) Slimani 1994.
The taxonomy of Aloinella, Guillauminia and Lemeea (Aloaceae)
Authors: Smith Gideon F. , van Wyk Ben‐Erik , Mössmer Marthina , Viljoen Alvaro
Published: April 2006

Smith, G. F., Wyk, B. E. van, Mössmer, M. & Viljoen, A.: The taxonomy of Aloinella, Guillauminia and Lemeea (Aloaceae). – Taxon 44: 513‐517. 1995. – ISSN 0040‐0262.

The recent reinstatement of the genera Guillauminia and Lemeea (Aloinella Lemée non Cardot) in the Aloaceae is discussed. It is concluded that both should remain in the synonymy of Aloe L.
Lectotypification of Cimicifuga foetida (Ranunculaceae)
Authors: Compton James A. , Jury Stephen L.
Published: April 2006

Compton, J. A. & Jury, S. L.: Lectotypification of Cimicifuga foetida (Ranunculaceae). – Taxon 44: 603‐605. 1995. – ISSN 0040‐0262.

Cimicifuga foetida, the type of the generic name Cimicifuga, is here lectotypified by a specimen in the Linnaean collections at Stockholm (S).
The identity and neotypification of Endosteira Turcz. (Rhizophoraceae)
Authors: Dorr L. J.
Published: April 2006

Dorr, L. J.: The identity and neotypification of Endosteira Turcz. (Rhizophoraceae). – Taxon 43: 639‐640. 1994. – ISSN 0040‐0262.

Endosteira was originally described as a genus of the Tiliaceae. The name of its sole species, E. oppositifolia, is here neotypified and becomes a synonym of Cassipourea guianensis Aubl. (Rhizophoraceae).
Specimen deaccessions from the Missouri Botanical Garden Herbarium during the tenure of Robert E. Woodson (1948‐1963)
Authors: Solomon James C.
Published: April 2006

Solomon, J. C: Specimen deaccessions from the Missouri Botanical Garden Herbarium during the tenure of Robert E. Woodson (1948‐1963). – Taxon 47: 663‐680. 1998. – ISSN 0040‐0262.

During the period 1948‐1963, a minimum of 127, 108 mounted herbarium specimens were deaccessioned from the Missouri Botanical Garden Herbarium under the direction of Robert E. Woodson and distributed by exchange or sale to at least 48 botanical institutions throughout the world. Some of these specimens were true duplicates, but many, including some types, were not. In addition, an unknown quantity of specimens, numbering perhaps in the tens of thousands, was discarded. A summary of the number of specimens deaccessioned, the nature of the material sent, and the recipient institutions is presented. An account is also given of the 63,853 specimens that have been returned to the Garden and reincorporated into the collection.
On the identity of the enigmatic Thalictrum morisonii (Ranunculaceae)
Authors: Hand R.
Published: April 2006

Hand, R.: On the identity of the enigmatic Thalictrum morisonii (Ranunculaceae). – Taxon 47: 717‐720. 1998. – ISSN 0040‐0262.

The type specimen of Thalictrum morisonii C. C. Gmel. is missing. An illustration designated as lectotype, supported by a fitting epitype also desiganted here, belongs to T. flavum L. T. morisonii in the sense of Flora europaea and T. exaltatum Gaudin are the same as T. lucidum L.
Cerviculospermum, a new name for a genus of Palaeozoic seeds
Authors: Pant Divya Darshan , Nautiyal Devendra Dutt , Tiwari Satyendra Prakash
Published: April 2006

Pant, D. D., Nautiyal, D. D. & Tiwari, S. P.: Cerviculospermum, a new name for a genus of Palaeozoic seeds. Taxon 47: 721. 1998. – ISSN 0040‐0262.

A new name, Cerviculospermum, and a new combination, C. ovale, are proposed. The replaced name, Collospermum, is a junior homonym of a name currently used for a genus of Liliaceae.
A taxonomic revision of the Loropetalum‐Tetrathyrium complex and its systematic position in the Hamamelidoideae, based on morphology and ITS sequence data
Authors: Yu‐xing Feng , Zhi‐duan Chen , Xiao‐quan Wang , Kai‐yu Pan , De‐yuan Hong
Published: April 2006

Feng, Y. X., Chen, Z. D., Wang, X. Q., Pan, K. Y. & Hong, D. Y.: A taxonomic revision of the Loropetalum‐Tetrathyrium complex and its systematic position in the Hamamelidoideae, based on morphology and ITS sequence data. – Taxon 48: 689‐700. 1999. – ISSN 0040‐0262.

Based on analysis of morphological characters and ITS sequences, a taxonomic revision of Loropetalum and Tetrathyrium is presented. Oliver's merging of Tetrathyrium under Loropetalum is corroborated. L. subcapitatum, L. indicum, and T. simaoense are reduced to synonymy under L. chinense. E. Asian Corylopsis is sister of Loropetalum among the 12 genera of Hamamelidoideae studied, which form four monophyletic clades coextensive with three tribes and one subtribe of Endress: Corylopsideae, Loropetalinae, Fothergilleae, and Eustigmateae.
Publication details for Pfeiffer's Nomenclator botanicus
Authors: Rye Barbara L. , Wilson Paul G.
Published: April 2006

Rye, B. L. & Wilson, P. G.: Publication details for Pfeiffer's Nomenclator botanicus. –Taxon 48: 793‐795. 1999. – ISSN 0040‐0262.

This article makes minor corrections to the dates given in Stafleu & Cowan's Taxonomic literature of 1983 for reviews of the many parts of Pfeiffer's Nomenclator botanicus of 1871‐1875 and provides a table showing the most likely page numbers in each part.
The typification of Cuphea (Lythraceae): C. viscosissima versus C. decandra
Authors: Molero Julià , Zijlstra Gea
Published: April 2006

Molero, J. & Zijlstra, G.: The typification of Cuphea (Lythraceae): C. viscosissima versus C. decandra. – Taxon 48: 797‐799. 1999. – ISSN 0040‐0262.

The nomenclatural type of the name Cuphea was stated by Graham to be C. decandra, but there is an earlier type designation by Swart who chose C. viscosissima. Both options are discussed, and it is concluded that Swart's typification must stand. A lectotype of C. viscosissima is designated, superseding the neotype proposed by Graham.
Echinoplaca vezdana (Ostropales: Gomphillaceae): a new lichenised fungus
Authors: Lücking Robert , Kalb Klaus
Published: April 2006

Lücking, R. & Kalb, K.: Echinoplaca vezdana: a new lichenised fungus. ‐ Taxon 50: 837–840. 2001. ‐ ISSN 0040‐0262.

The lichenised fungus Echinoplaca vezdana from the Philippines is described and illustrated. It has a comparatively large thallus, large apothecia, and 2–4 muriform ascospores per ascus. The new taxon is closely related to E. diffluens, which differs in having transversely septate ascospores. The two species form another pair of morphologically similar taxa differing in ascospore types of which five were previously known. Echinoplaca vezdana is dedicated to Antonín Vňzda, one of the outstanding lichen taxonomists of the 20th century, on the occasion of his recent 80th birthday.
Discovering the plant world
Authors: Prance Ghillean T.
Published: April 2006

Prance, G. T.: Discovering the plant world. – Taxon 50: 345–359. 2001. – ISSN 0040‐0262.

The last fifty years have been a time of accelerated plant collection, especially in the tropics. However, this is a race against time since the destruction of natural habitats has also increased dramatically. The rate at which collecting is still adding new species of flowering plants indicates that the inventory is not nearly complete, and that the past estimates of total species numbers are low and should be increased to 320,000. The production of florulas and quantitative inventories of small areas of the tropics, accompanied by intensive fieldwork, has greatly helped to improve the level of inventory. Future collecting should be carefully targeted towards areas that are particularly threatened, such as those defined as hotspots, and also collection of rare species rather than repeated over‐collection of widely distributed common taxa. Future collecting should also gather material for ancillary studies such as molecular work and evolutionary development.
Nomenclature of genera and subdivisions of genera withinScleriaP.J. Bergius (Cyperaceae)
Authors: Camelbeke Konraed , Zijlstra Gea , Goetghebeur Paul
Published: April 2006

Camelbeke, K., Zijlstra, G. & Goetghebeur, P.: Nomenclature of genera and subdivisions of genera withinScteriaP.J. Bergius (Cyperaceae). – Taxon 50: 479–486. 2001. – ISSN 0040‐0262.

A list of effectively published names of genera and subdivisions of genera included or formerly included in the genusScleriais provided, together with their status and types. The following names are here typified:HymenolytrumSchrad. ex Nees,MacrolomiaSchrad. ex Nees,MastigoscleriaNees,OmoscleriaNees, andTrachylomiaNees;Scleriasect.FoveolidiaRaf., sect.MargaleiaRaf., sect.PaniculataePax, and sect.RuguniaRaf.;Scleriaser.PolystachyaeBenth. and ser.SubspicataeBenth.;Scleria[unranked]SpicataeBoeck., and [unranked]TuberculataeCore. Moreover, two excluded names are typified:CryptangiumSchrad. ex Nees, andScleriaser.AxillaresBenth.
Neotypification of the name Geum pyrenaicum (Rosaceae)
Authors: Garmendia Félix Muñoz , Laínz Manuel , Aedo Carlos
Published: April 2006

Muñoz Garmendia, F., Laíz, M. & Aedo, C: Neotypification of the name Geum pyrenaicum (Rosaceae). ‐ Taxon 47: 113–114.1998. ‐ ISSN 0040‐0262.

There is no extant original material for Geum pyrenaicum Mill., a name sometimes attributed to Willdenow. Although the name has often been misapplied to the hybrid G. montanum × G. rivale by Central European authors in the past, and may have been so used by both Miller and Willdenow, its universal use for a Pyrenean‐Cantabrian endemic for 150 years makes it advisable to fix that application by designation of an appropriate neotype.
Colysis ×beddomei (Polypodiaceae, Pteridophyta): a new interspecific fern hybrid from India, Burma and China
Authors: Manickam V. S. , Irudayaraj V. , Rajkumar S. Dominic
Published: April 2006

Manickam, V. S., Irudayaraj, V. & Rajkumar, S. D.: Colysis ×beddomei (Polypodiaceae, Pteridophyta): a new interspecific fern hybrid from India, Burma and China. – Taxon 46: 265‐268. 1997. – ISSN 0040‐0262.

The new fern hybrid Colysis ×beddomei Manickam & Irudayaraj (Colysis decurrens × C. hemionitidea) is described and illustrated. It was first collected in south India by Beddome, before 1883, and was then assigned to Gymnopteris variabilis. The morphological variation of the hybrid is discussed on the basis of newly collected material from the same area and of herbarium specimens from Burma and China.
A chemotaxonomic and biochemical evaluation of the identity of Aloe candelabrum (Aloaceae)
Authors: Viljoen Alvaro M. , Van Wyk Ben‐Erik , van der Bank Herman , Smith Gideon F. , van der Bank Michelle
Published: April 2006

Viljoen, A. M., Van Wyk, B‐E., Van der Bank, H., Smith, G. F. & Van der Bank, M.: A chemotaxonomic and biochemical evaluation of the identity of Aloe candelabrum (Aloaceae). – Taxon 45: 461‐471. 1996. – ISSN 0040‐0262.

In situ morphological analysis of plants from the entire distribution area supports the assumption that Aloe candelabrum, by its reproductive and vegetative characters, falls well within the taxonomic concept of A. ferox. The identical chemical composition of leaf exudate with regard to secondary compounds (chromone and anthrone derivatives) supports this conclusion. Gene products at 23 enzyme‐coding loci, analyzed by horizontal starch gel‐electrophoresis, revealed no fixed allele differences between A. candelabrum and A. ferox. The differences on which the two species were previously separated can be explained as local variation within a single and widespread taxon. A. candelabrum should therefore be subsumed under A. ferox.
Biogeographical and molecular observations onPhaseolus glabellus (Fabaceae, Phaseolinae)and its taxonomic status
Authors: Schmit V. , Debouck D. G. , Baudoin J. P.
Published: April 2006

Schmit, V., Debouck, D. G. & Baudoin, J. P.: Biogeographical and molecular observations onPhaseolus glabellus (Fabaceae, Phaseolinae)and its taxonomic status. – Taxon 45: 493‐501. 1996. – ISSN 0040‐0262.

The wild, red‐floweredPhaseolus glabellusis generally considered either as a species of theP. coccineuscomplex or as a subspecies ofP. coccineus.Biogeographic considerations as well as experimental hybridization, seed storage protein electrophoresis and cpDNA polymorphism point at its isolated taxonomic position and distinctness fromP. coccineus.The position ofP. glabellusinPhaseolusand its relationships with the remaining taxa of theP. coccineuscomplex are discussed.
A simple method for computerizing taxonomic treatments
Authors: Whittemore Alan T.
Published: April 2006

Whittemore, A. T.: A simple method for computerizing taxonomic treatments. – Taxon 45: 503‐511. 1996. – ISSN 0040‐0262.

Standard taxonomic treatments are very well adapted to computerization. A method is presented for producing taxonomic treatments using standard commercial software (spreadsheets and word processors). The data from morphological descriptions and other elements of the treatments are stored in the spreadsheet with taxa as rows and characters as columns, and the descriptions are generated using a print merge routine, available in most word processors. Departures from parallelism necessitated by structural differences between taxa or by missing data are easily accommodated using conditional statements in the print merge. Examples are given to illustrate the approach. Treatments prepared in this way are easy to edit for parallelism and internal consistency, and format changes can be entered once for incorporation throughout the treatment. This approach can be used to produce taxonomic treatments in an easily editable form, or as a framework for developing a data structure for use in a database or specialized taxonomy program.
The publication date of Kaktus‐ABC
Authors: Hjertson Mats , Eggli Urs
Published: April 2006

Hjertson, M. & Eggli, U.: The publication date of Kaktus‐ABC. – Taxon 45: 513‐514. 1996 – ISSN 0040‐0262.

Correspondence from the publisher shows that the actual publication date of Backeberg & Knuth's Kaktus‐ABC is 12 Feb 1936, not 31 Dec 1935 as stated in the book.
Species of Monnina with names first published by Bonpland in Hebeandra (Polygalaceae)
Authors: Eriksen Bente
Published: April 2006

Eriksen, B.: Species of Monnina with names first published by Bonpland in Hebeandra (Polygalaceae). – Taxon 45: 631‐640. 1996. – ISSN 0040‐0262.

Due to a misunderstanding new species of Monnina collected by Humboldt and Bonpland were described twice and under different generic names. In 1808 Bonpland described the genus Hebeandra to accomodate 16 new species collected by Humboldt and himself in Central and South America, ignoring the genus Monnina established by Ruiz and Pavón ten years before. Kunth, unaware of Bonpland's paper, republished the species in 1823, based on the same collections, but under Monnina. The epithets were partly those used by Bonpland, partly his own. This paper reviews the resulting nomenclatural chaos. Typification of the names involved is discussed, and lectotypes are designated when appropriate. Six traditionally accepted specific names will change unless conservation, proposed elsewhere, is granted.
Hierarchical models, reticulate evolution and the inevitability of paraphyletic supraspecific taxa
Authors: Sosef M. S. M.
Published: April 2006

Sosef, M. S. M.: Hierarchical models, reticulate evolution and the inevitability of paraphyletic supraspecific taxa. – Taxon 46: 75‐85. 1997. – ISSN 0040‐0262.

A phylogenetic tree can be subdivided according to a monophyletic hierarchical model, in which only monophyletic units figure, or according to a “Linnaean” hierarchical model in which both mono‐ and paraphyletic units occur. Most present‐day phylogeneticists try to fit the monophyletic model within the set of nomenclatural conventions that fit the Linnaean model. However, the two models are intrinsically incongruent. The monophyletic model requires a system of classification of its own, at variance with currently accepted conventions. Since, however, the monophyletic model is unable to cope with reticulate evolutionary relationships, it is unsuited for the classification of nature. The Linnaean model is to be preferred. This renders the acceptance of paraphyletic supraspecific taxa inevitable.
A nomenclatural checklist of supraspecific names in Taraxacum
Authors: Kirschner Jan , Štňpánek Jan
Published: April 2006

Kirschner, J. & Štňpánek, J.: A nomenclatural checklist of supraspecific names in Taraxacum. –Taxon 46: 87‐98. 1997. – ISSN 0040‐02

Names of subdivisions of the genus Taraxacum are listed and critically analysed. Validity and legitimacy are determined, all valid names are given types, and type specimens are selected and quoted where available. Comments are confined to the nomenclatural status of the names; for important taxonomic synonyms the accepted names are given, and names considered correct are highlighted.
Systematic plant morphology and anatomy‐50 years of progress
Authors: Endress Peter K. , Baas Pieter , Gregory Mary
Published: April 2006

Endress, P. K., Baas, P. & Gregory, M.: Systematic plant morphology and anatomy –50 years of progress. ‐ Taxon 49: 401–434. 2000. ‐ ISSN 0040‐0262.

Fifty years of comparative and systematic plant morphology and anatomy are reviewed. Thanks to new techniques (TEM, SEM, cinematography, molecular analyses), and new methods and concepts (cladistics, evolutionary paleobotany, molecular systematics and molecular developmental genetics), plant systematics and comparative structural studies saw major progress. The integration of micromorphological with molecular data has led to an increasingly robust phylogeny of the angiosperms. Successes and failures in the premolecular era of phylogenetic classification using morphological and/or anatomical markers only are illustrated with examples. With the new phylogenetic framework, it becomes possible to trace the evolution of characters more accurately than before. Central problems in comparative and systematic structural studies are the meaning of homology and character definition; some aspects have been elucidated but new ones have appeared with the molecular dimension in evolutionary biology. In vegetative anatomy, the integration of ecological and systematic anatomy into “ecophyletic” anatomy has led to a better understanding of the driving forces behind evolutionary diversification of wood and leaf anatomical attributes. However, the intertwining of ecological (extrinsic) and organisational (intrinsic) constraints in the origin of form remains a major challenge for future studies.
Eocooksonia, a new substitute name for Cooksonella (Cooksoniaceae‐Rhyniophyta)
Authors: Doweld Alexander B.
Published: April 2006

Doweld, A. B.: Eocooksonia, a new substitute name for Cooksonella (Cooksoniaceae‐Rhyniophyta). ‐ Taxon 49: 547. 2000. ‐ ISSN 0040‐0262.

The later homonym Cooksonella M. Senkevitsch, 1978 (fossil rhyniophyte) [non E. Nagy, 1965 (acritarcha)] is replaced by a new generic name Eocooksonia Doweld.
Pollen morphology and relationships of Setchellanthus caeruleus (Setchellanthaceae)
Authors: Tomb A. Spencer
Published: April 2006

Tomb, A. S.: Pollen morphology and relationships of Setchellanthus caeruleus (Setchellanthaceae). – Taxon 48: 285‐288. 1999. – ISSN 0040‐0262.

Pollen of Setchellanthus caeruleus was studied by light, scanning electron, and transmission electron microscopy and found to differ profoundly from that of potentially related families such as the Brassicaceae, Capparaceae, Caricaceae, Cistaceae (Helianthemum canadense, here re‐investigated and found to have pollen shed in tetrads), and Limnanthaceae. These differences support the segregation of S. caeruleus into a new separate family.
Vegetative anatomy and relationships of Setchellanthus caeruleus (Setchellanthaceae)
Authors: Carlquist Sherwin , Miller Regis B.
Published: April 2006

Carlquist, S. & Miller, R. B.: Vegetative anatomy and relationships of Setchellanthus caeruleus (Setchellanthaceae). – Taxon 48: 289‐302. 1999. – ISSN 0040‐0262.

On account of its distinctive features, Setchellanthus cannot be included within any of the families of glucosinolate‐producing plants. Features unknown in any of these families include abundant vasicentric tracheids, abaxial axial parenchyma, and only short uniseriate rays (composed of upright cells) in wood; and the presence of wide‐helix tracheary elements in leaves. Wood offers the greatest number of phyletically significant features, and wood of Capparaceae offers many similarities, although the wood of Helianthemum (Cistaceae) is even more like that of Setchellanthus. Despite the fact that no myrosin cells were observed in Setchellanthus, it appears closest, on the basis of present information, to the glucosinolate‐producing families.
Riddell, Sullivant, and the early botanical exploration of Franklin County, Ohio, U.S.A. (1832‐1840)
Authors: Lowden Richard M.
Published: April 2006

Lowden, R. M.: Riddell, Sullivant, and the early botanical exploration of Franklin County, Ohio, U.S.A. (1832‐1840). – Taxon 46: 689‐703. 1997. – ISSN 0040‐0262.

Two frontier botanists, John Leonard Riddell and William Starling Sullivant, treated the vascular flora of Franklin County, Ohio, U.S.A., creditably despite the scarcity of proper books and the lack of opportunity to consult herbaria. Their vascular plant catalogues document the first species (and their habitats) discovered in this central Ohio county, now the site of the state capital. A list is presented of 24 vascular plant taxa first named and described from Franklin County.
The identity of Kobresia littledalei (Cyperaceae)
Authors: Zhang Shu‐ren
Published: April 2006

Zhang, S. R.: The identity of Kobresia littledalei (Cyperaceae). – Taxon 48: 15‐16. 1999.–ISSN 0040‐0262.

Kobresia littledalei, published by C. B. Clarke in 1908, was so far misunderstood by several botanists. The name is lectotypified and accepted for a hitherto neglected separate species, here redescribed.
A protective hardboard folder for storing herbarium specimens
Authors: Shchepanek Michael J.
Published: April 2006

Shchepanek, M. J.: A protective hardboard folder for storing herbarium specimens. – Taxon 48: 17‐21. 1999. – ISSN 0040‐0262.

Many herbaria store their most valuable botanical specimens, such as types, mounted on herbarium paper, within closed or semi‐closed pliable cardboard folders. In order to minimise the risk of damage through handling and shipping, an archival hardboard folder was designed, to provide maximum protection. The design accommodates herbarium sheets of different sizes and specimens of various thickness. The folders can be made from materials available from art supply stores.
Typification of the name Regelia and transfer of Melaleuca sprengelioides to Beaufortia (Myrtaceae)
Authors: Craven L. A.
Published: April 2006

Craven, L. A.: Typification of the name Regelia and transfer of Melaleuca sprengelioides to Beaufortia (Myrtaceae). – Taxon 48: 53‐55. 1999. – ISSN 0040‐0262.

Regelia, through its type R. ciliata, is here typified by a specimen that enables current usage of the name to be preserved. The name that has been considered by some botanists to be the base name of R. ciliata, Melaleuca sprengelioides, represents a species of Beaufortia and is newly transferred to that genus.
Impact of outgroup inclusion on estimates by parsimony of undirected branching of ingroup phylogenetic lines
Authors: Baum Bernard R. , Estabrook George F.
Published: April 2006

Baum, B. R. & Estabrook, G. F: Impact of outgroup inclusion on estimates by parsimony of undirected branching of ingroup phylogenetic lines. – Taxon 45: 243‐257. 1996. – ISSN 0040‐0262.

Some of the effects of including outgroup taxa on the branching pattern of the ingroup taxa are revealed by an artificial example, and illustrated with a more complex natural example involving the grass genus Kengyilia. To reduce the total number of changes required by a branching pattern, parsimony may prefer to reduce the number of changes on temporally long phyletic lines to more distant outgroups while increasing changes on temporally short phyletic lines within the ingroup. This may have the effect of bringing the ancestors that define monophyletic groups within the ingroup down to the phyletic line to the outgroup, which converts them to paraphyletic groups. Thus the inclusion of outgroup taxa during parsimony may alter the branching pattern of the ingroup to destroy distinct monophyletic groups and instead create nested series of monophyletic groups, reminiscent of the chaining properties of some phenetic methods. If similarities between ingroup and outgroup are true homoplasies, then removal of these homoplasies will produce error. However, parsimony estimates of ingroup may produce bogus monophyletic groups because no account has been made of the ingroup's most recent common ancestor.
Biogeography ofNothofagussupports the sequence of Gondwana break‐up
Authors: Swenson Ulf , Hill Robert S. , McLoughlin Stephen
Published: April 2006

Swenson, U., Hill, R. S. & McLoughlin, S.: Biogeography ofNothofagussupports the sequence of Gondwana break‐up. ‐ Taxon 50: 1025–1041. 2001. ‐ ISSN 0040–0262. The Austral biota reveals many links between Australasia and South America that have challenged biogeographers for many years.Nothofagus, the Southern Beech, is probably the classical example. With the general acceptance of continental drift, the break‐up of Gondwana is regarded as primarily responsible for many disjunct patterns expressed in the Southern Hemisphere biota. Vicariance biogeography is the principal tool used to investigate biogeographic patterns of extant plant groups, resulting in areagrams or general area cladograms. These are often at odds with current geological knowledge, and on this basis, alternative hypotheses of area relationships and geological history have, therefore, been suggested. One such areagram was recently advocated by Linder & Crisp (1995) in a biogeographic analysis ofNothofagus.Three explanations, often in combination, account for incongruence: long‐distance dispersals, extinctions, and erroneous geological models. All of these parameters ought to be considered in the analysis. Here we report the result of a historical biogeographic analysis ofNothofaguswhere we compare the reconciled trees between a well‐supportedNothofagusphylogeny and two geological hypotheses: (1) the current view of Gondwana break‐up, and (2) the areagram by Linder & Crisp. Our analysis makes use of extant and extinct taxa, as well as the assumption of long‐distance dispersals as defined by maximized vicariance. Our results show thatNothofagusexisted prior to the break‐up of Gondwana and, most importantly, its present distribution supports, and is dependent upon, the traditional break‐up sequence of East Gondwana, compatible with three vicariance events. The areagram, conceived as an alternative geological hypothesis, presents a more parsimonious solution, but fails to explain numerous past distributions in areas such as Antarctica, South America, and Tasmania. We therefore recommend a conservative approach to use (general) areagrams in historical biogeography.
Typification of Linnaean names of taxa of Verbenaceae s.str. described from the Greater Antilles
Authors: Santos Isidro E. Méndez , Cafferty Steve
Published: April 2006

Méndez Santos, I. E. & Cafferty, S.: Typification of Linnaean names of taxa of Verbenaceae s.str. described from the Greater Antilles. – Taxon 50: 1137–1141. 2001. – ISSN 0040–0262.

Lectotypes, neotypes or epitypes are designated for nine names of taxa described by Linnaeus in Citharexylum, Lantana, and Verbena, and currently placed in the family Verbenaceae s.S., that are found in the Greater Antilles.
Log-concavity and log-convexity in passage time densities of diffusion and birth-death processes
Authors: Keilson Julian
Published: April 2006

Diffusion and birth-death processes have basic theoretical and practical importance for statistics. Insight into the structure of transition distributions and passage time distributions for such processes has been given in recent years by Feller. Karlin, Kemperman, D. G. Kendall, Reuter and many others. An elementary account of this work and partial bibliography has been given elsewhere ([9], [10)]. Certain key passage time densities and sojourn time densities for such processes have a simple property of log-concavity or log-convexity and associated unimodality. Such properties provide information on the character of distributions unavailable from the spectral representations, Laplace transforms and series of convolutions at hand. These properties may also have value for purposes of estimation and optimization.
On Monte Carlo algebra
Authors: Gordon Richard
Published: April 2006

A Monte Carlo method is proposed and demonstrated for obtaining an approximate algebraic solution to linear equations with algebraic coefficients arising from first order master equations at steady state. Exact solutions are hypothetically obtainable from the spanning trees of an associated graph, each tree contributing an algebraic term. The number of trees can be enormous. However, because of a high degeneracy, many trees yield the same algebraic term. Thus an approximate algebraic solution may be obtained by taking a Monte Carlo sampling of the trees, which yields an estimate of the frequency of each algebraic term. The accuracy of such solutions is discussed and algorithms are given for picking spanning trees of a graph with uniform probability. The argument is developed in terms of a lattice model for membrane transport, but should be generally applicable to problems in unimolecular kinetics and network analysis. The solution of partition functions and multivariable problems by analogous methods is discussed.
Maintainability of structures in Markov chain models under recruitment control
Authors: Davies G. S.
Published: April 2006

We consider a fixed size Markov chain model which suffers losses and admits controlled recruitment. The family of n-step maintainable structures is described geometrically and examined.
Waiting times without memory
Authors: Durrett Richard T. , Ghurye S. G.
Published: April 2006

A waiting time without memory, or age-independent residual life-time, is a positive-valued random variable T with the property that for any x, y > 0, given that T >x, the conditional probability of T >x +y is the same as the unconditional probability of T >y; in other words, the physical process operates as if it has no memory concerning the successive occurrences of a certain event. The paper investigates the consequences of defining the property of lack of memory on more general time-domains than the positive reals. As a side issue, there is discussion of a stochastic variation of Cauchy's functional equation.
The single-server queue with random service output
Authors: Boxma O. J.
Published: April 2006

In this paper a problem arising in queueing and dam theory is studied. We shall consider a G/G*/1 queueing model, i.e., a G/G/1 queueing model of which the service process is a separable centered process with stationary independent increments. This is a generalisation of the well-known G/G/1 model with constant service rate.

Several results concerning the amount of work done by the server, the busy cycles etc., are derived, mainly using the well-known method of Pollaczek. Emphasis is laid on the similarities and dissimilarities between the results of the ‘classical’ G/G/1 model and the G/G*/1 model.
Resource allocation in speculative chemical research
Authors: Gittins J. C.
Published: April 2006

A stochastic theory is given for speculative industrial chemical research. It is shown how the theory may be used to suggest a suitable balance between long-term and short-term projects.
Optimal feedback control of stochastic McShane differential systems
Authors: Ahmed N. U. , Teo K. L.
Published: April 2006

In this paper, the optimal control problem of system described by stochastic McShane differential equations is considered. It is shown that this problem can be reduced to an equivalent optimal control problem of distributed parameter systems of parabolic type with controls appearing in the coefficients of the differential operator. Further, to this reduced problem, necessary conditions for optimality and an existence theorem for optimal controls are given.
Asymptotic distribution for the coupon — collector's and sampling-tagging problems, when tagging affects catchability
Authors: Samuel-Cahn Ester
Published: April 2006

The coupon-collector's and sampling tagging problems are considered, under the model that each tagged element is γ > 0 times as likely to be caught at the next stage as every untagged element. Let WN(γ, k) and SN(γ, j) denote, respectively, the waiting time until k + 1 distinct elements are obtained, and the number of distinct elements in a sample of size j, when the population size is N. Complete characterisations are obtained for the limiting distributions of WN (γ, k) and SN(γ, j), in terms of the rates at which k and j tend to infinity with N.
A further note on duality of random walks
Authors: Barnett N. S.
Published: April 2006

A multi-dimensional generalisation of a well-known duality relation in random walk theory is given.
On the transient waiting times for a GI/M/1 priority queue
Authors: Dalen G. , Natvig B.
Published: April 2006

In this paper we consider the GI/M/1 queueing model with infinite waiting-room capacity. The customer arriving at t = 0 will find k — 1 customers waiting. The latter customers belong to a second priority class, whereas the ones arriving in [0,∞) belong to a first priority class and have the higher priority. Within each class we have a first-in-first-out queueing discipline. A customer, once at the service-point, remains there until his service is completed. Then the next customer for service is the one of highest priority among those queueing.

For this model we derive the transient waiting times for customers belonging to both priority classes. The results are of special interest in appointment systems where customers may not turn up.
The discrete-time single-server queue with time-inhomogeneous compound Poisson input and general service time distribution
Authors: Minh Do Le
Published: April 2006

This paper studies a discrete-time, single-server queueing model having a compound Poisson input with time-dependent parameters and a general service time distribution.

All major transient characteristics of the system can be calculated very easily. For the queueing model with periodic arrival function, some explicit results are obtained.
Intercept lengths of random probes through boxes
Authors: Coleman Rodney
Published: April 2006

The distribution and its moments are given of the length of the intercept made by a random probe through a box having perpendicular edge lengths a, b and c. Three types of random probe are considered.
A strong law of Erdös-Rényi type for cumulative processes in renewal theory
Authors: Steinebach Josef
Published: April 2006

Let {Nt}t >0 be a renewal counting process (cf. Parzen (1962), p. 160) with underlying failure times let be a sequence of non-negative random variables and {Zt}t >0 an associated cumulative process, i.e. if Nt = 1, 2, …, and Zt = 0, if Nt = 0. By convention set Z0 = 0. Consider the maximum increment of the process {Zt}t >0 in [0, T] over a time K, 0 < K < T, divided by K. Under appropriate conditions it is shown that for a wide range of numbers a there exist constants C(a), uniquely determined by a and the distributions of the Xi's and Yj's, such that D(T, C log T) converges to a with probability 1. This result provides a renewal theoretic variant of Erdös and Rényi's (1970) ‘new law of large numbers’.
A note on seasonal Markov chains with gamma or gamma-like distributions
Authors: Lloyd E. H. , Saleem S. D.
Published: April 2006

Weighted sums defined on a Markov chain (MC) are important in applications (e.g. to reservoir storage theory). The rather intractable theory of such sums simplifies to some extent when the transition p.d.f. of the chain {Xt} has a Laplace transform (LT) L(Xt+1; θ |Χ t=x) of the ‘exponential' form H(θ) exp{ – G(θ)x}. An algorithm is derived for the computation of the LT of Σat,Χ t for this class, and for a seasonal generalization of it.

A special case of this desirable exponential type of transition LT for a continuous-state discrete-time MC is identified by comparison with the LT of the Bessel distribution. This is made the basis for a new derivation of a gamma-distributed MC proposed by Lampard (1968).

A seasonal version of this process is developed, valid for any number of seasons.

Reference is made to related chains with three-parameter gamma-like distributions (of the Kritskii–Menkel family) that may be generated from the above by a simple power transformation.
The variance of duration of stay in an absorbing Markov process
Authors: Rust Philip F.
Published: April 2006

Given a stationary Markov process with s transient states and r absorbing states, a matrix infinite series solution is presented for the variance of duration of stay in state j within the interval [0, t), given initial state i. Closed forms are derived for absorbing states, and for transient states if eigenvalues are real and distinct. Several relationships among Markov matrices are presented.
On limit distributions for one- and two-sample Kolmogorov–Smirnov type statistics
Authors: Geller Nancy L.
Published: April 2006

Several new limit theorems for one- and two-sample statistics of the Kolmogorov-Smirnov type are obtained. These generalize results of Takács, Vincze, and others. The proofs combine combinatorial and weak convergence techniques.
The basic structures of Voronoi and generalized Voronoi polygons
Authors: Miles R. E. , Maillardet R. J.
Published: April 2006

For each particle in an aggregate of point particles in the plane, the set of points having it as closest particle is a convex polygon, and the aggregate V of such Voronoi polygons tessellates the plane. The geometric and stochastic structure of a random Voronoi polygon relative to a homogeneous Poisson process is specified.

Similarly, those points of the plane possessing the same n nearest particles constitute a convex polygon cell in the generalized Voronoi tessellation 𝒱 (n = 2, 3, ·· ·). In fact, 𝒱 = 𝒱1, but to ease exposition n always takes the values 2, 3, ···. A key geometrical lemma elucidates the geometric structure of members of 𝒱n, showing it to be simpler in one important respect than that of members of 𝒱; in that, for each such N-gon of given ‘type', there is a uniquely determined set of N generating particles. The corresponding jacobian is given, and used to derive the basic ergodic structure of 𝒱n relative to a homogeneous Poisson process.

Unlike 𝒱 no 𝒱n contains any triangles. As n →∞, the vertices of the quadrangles of 𝒱n tend to circularity, so that the sums of their opposite interior angles tend to π.
Probability models for liberation
Authors: Davy Pamela J.
Published: April 2006

An index lying between 0 and 1 is presented to describe the degree of liberation (or separation) of one component of a particulate material. It is shown how the index is related to the covariance function of the material, the distribution of shapes and sizes of the particles and to the interaction between fracture surfaces and the structure of the material. The variation of the index with the extent of crushing is investigated, together with the problem of stereological estimation. The index is evaluated for some particular probability models.
Cyclic behaviour and asymptotic stability of non-homogeneous Markov systems
Authors: Vassiliou P.-C. G.
Published: April 2006

In this paper we study the cyclic behaviour of non-homogeneous Markov systems, i.e. the behaviour of the system under the assumption of periodic sequences of transition matrices, input probabilities, output probabilities and total numbers in the system. We provide a general theorem for the limiting structure of such a system under the cyclic behaviour. We also study the asymptotic stability of non-homogeneous Markov systems and theorems are given which characterize asymptotic stability. An application of the above results is given for a British firm, BS.
Presentation of phase-type distributions as proper mixtures
Authors: Assaf David , Langberg Naftali A.
Published: April 2006

It is shown that any phase-type distribution can be represented as a proper mixture of two distinct phase-type distributions. Using different terms, it is shown that the class of phase-type distributions does not include any extreme ones. A similar result holds for the subclass of upper-triangular phase-type distributions.
The association in time of a Markov process with application to multistate reliability theory
Authors: Hjort Nils Lid , Natvig Bent , Funnemark Espen
Published: April 2006

A series of bounds for the availability and unavailability in a fixed time interval, I, for a system of maintained, interdependent components are given in Natvig (1980) in the traditional binary case, and in Funnemark and Natvig (1985) in the multistate case. For the special case of independent components the only assumption needed to arrive at these bounds is that the marginal performance process of each component is associated in I. When these processes are Markovian and binary, a sufficient condition for this to hold is given by Esary and Proschan (1970). In the present paper we generalize this condition to the multistate case, and give an equivalent and much more convenient condition in terms of the transition intensities.
Stabilité de la récurrence nulle pour certaines chaines de Markov perturbées
Authors: Cocozza-Thivent C. , Kipnis C. , Roussignol M.
Published: April 2006

We investigate how the property of null-recurrence is preserved for Markov chains under a perturbation of the transition probability. After recalling some useful criteria in terms of the one-step transition nucleus we present two methods to determine barrier functions, one in terms of taboo potentials for the unperturbed Markov chain, and the other based on Taylor's formula.