bluuebunny/crossref_metadata_2025_split huggingface dataset:
BIOSYSTEMATIC PATHWAYS ANNO 1969
Authors: Stafleu Frans A. 
Published: April 2006

SummaryA review of some of the most recent developments in systematic biology. The present abundance of symposia in the field reflects the systematists' attempt to master an explosive development of knowledge in which many techniques and methods are used which formerly found little, if any, application in comparative biology. The information challenge is discussed with reference to modern processing methods and to abstracting. A shift in systematics from direct and visual characters to indirect, non‐visual data is apparent in many fields. The relation between numbers of known and possibly unknown taxa is illustrated by means of examples from the recent literature showing the rate of growth of our knowledge in various groups. The contributions by ultrastructural research, chemosystematics and molecular systematics are projected towards the future; other modern approaches in systematics (from ethology, ecology, micropaleontology, caryology, genecology) are mentioned briefly. The term biosystematics is used for evolutionary systematics of all living beings in the widest sense.
THE HANDLING OF CHARACTER VARIATION IN NUMERICAL TAXONOMY
Authors: McNeill J. 
Published: April 2006

SummaryThe problem of representing within‐OTU character variability in numerical taxonomy is considered and the limitations inherent in the restriction to single values, for example means or more seriously exemplar individuals, are emphasised. Jardine and Sibson's distinction between the attributes of individuals and the characters of populations or taxa is considered a useful one in its emphasis on the different treatment required for the comparison of individuals as OTUs as against that of groups. Existing methods of handling character variation are outlined and their limitations discussed. A new method, the character‐state frequency procedure, which can readily be incorporated into existing programs, is described and its effects on the analysis of two sets of data are outlined.
CIRCUMSCRIBING THE CONCEPT OF THE GENUS
Authors: Legendre Pierre 
Published: April 2006

SummaryThe present paper suggests that, despite its conceptual weakness, the cladistic approach to the delimitation of genera contains a valuable logical formalism. This logic could be applied to the dendrogram of the informational (genetic) similarity between the taxa to be classified. Even if this leads to a departure from a purely phyletic model of classification — that cannot be always maintained in a classification because of the internal limitations of the concept of classification — this approach corresponds much better to what we want a classification to be. A logical justification is given to phenetic taxonomy, when properly done.
FIFTY YEARS OF INTERNATIONAL BIOLOGY
Authors: Stafleu Frans A. 
Published: April 2006

SummaryA review of the development of the International Union of Biological Sciences (IUBS) since its establishment in 1919, preceded by some remarks on the origin of ‘biology’ as a discipline and on nineteenth century international cooperation in the natural sciences. After a rather slow start in the years before the second World War in which the activities were mainly centered upon the section of botany, IUBS developed fully after 1945 into a truly representative international forum for biology. The most pressing problems facing biology and IUBS in the early seventies — documentation and the environment — are briefly discussed with special reference to the change of attitude apparent in biology, as well as in biologists from ‘pure’ and ‘detached’ to a social and cultural ‘engagement‘.
CHEMOSYSTEMATICS: RECENT DEVELOPMENTS
Authors: Turner B. L. 
Published: April 2006

SummaryRecent developments in chemosystematics are reviewed with the conclusion that micro‐molecular data (essentially monomeric compounds such as flavonoids, alkaloids, terpenoids, amino acids, etc.) will prove most useful in resolving taxonomic problems at the generic level and lower while macromolecular data (polymeric compounds such as RNA, DNA, proteins, etc.) will prove most useful in resolving phyletic problems at the generic level and higher. Examples are given in which the two kinds of data have contributed to the resolution of such problems. Particular emphasis is placed upon the use of gas liquid chromatography in micro‐molecular studies, especially at the populational level. It is also concluded that protein‐band data and isoenzyme studies, as determined electrophoretically, because of the difficulty in establishing homology in the former and because of exceptional polymorphism in the latter, will be useful primarily at the specific level or lower. Developments have lagged in the application of serology and DNA hybridization to evolutionary problems in higher plant systematics and it appears that the most fruitful approach for unraveling phylogenetic pro. blems at the familial level or higher is that of animo‐acid sequence studies of metabolically important enzymes such as cytochrome c.
COMPUTERS IN BIOLOGICAL SYSTEMATICS, A NEW UNIVERSITY COURSE
Authors: Furlow J. J. , Morse L. E. , Beaman J. H. 
Published: April 2006

SummaryA new course covering major aspects of the use of computers in systematics was recently offered at Michigan State University. The course consisted of lectures delivered by 12 speakers, discussion sessions, and reports on student projects. Topics included computers and systematics, the Flora North America Program, specimen identification and key‐construction by computer, parallels between specimen identification and medical diagnosis, plant disease diagnosis by computer, information problems in paleontology, distribution mapping by computer, biometrics and statistical studies with computers, probabilistic approaches to specimen identification, computers as aids to teaching systematic biology, numerical taxonomy, the modeling of genetic and evolutionary systems, possible computerized nomenclatural aids, and biogeographical analysis with computers.
THE CYTOGEOGRAPHY OF THE LORANTHACEOUS MISTLETOES
Authors: Barlow B. A. , Wiens D. 
Published: April 2006

SummaryKnown chromosome numbers in the Loranthaceae are reviewed and 102 new records added. The basic number of the family is x = 12 and there has been progressive aneuploid reduction to x = 8. The early development of the family has been under temperate conditions in the Southern Hemisphere, where stocks with x = 12 and 11 became established in temperate South America and Australasia. Rapid aneuploid reduction continued after the establishment of strong continental isolation, establishing numbers of x = 9 and 8 in the Old and New Worlds respectively. Massive secondary radiation in the tropics has followed, involving the 12‐, 9‐ and 8‐paired stocks.Increase in chromosome size occurred during the tropical radiation, perhaps compensating for loss of recombination potential due to aneuploid reduction. Polyploidy is a rare and recent phenomenon in the history of the family, being documented in only two Central American taxa. One of these may be an autoploid.
GENETIC AFFINITIES BETWEEN HAWAIIAN AND MARQUESAN BIDENS (ASTERACEAE)
Authors: Gillett George W. 
Published: April 2006

SummaryGenetic affinities are reported between 6 Hawaiian taxa of Bidens and one species (B. ahnnei) indigenous to the Marquesas Islands. An argument is presented supporting the longdistance dispersal of Bidens from the New World to the Hawaiian Islands, and the later dispersal of this stock to the islands of Southeastern Polynesia.
ON “NUMERICAL CHEMOTAXONOMY”
Authors: Weimarck Gunnar 
Published: April 2006

SummaryThe use of chemical characteristics in plant taxonomy is briefly surveyed. Some types of numerical treatment of variation in chromatographically separated substances are discussed. The usefulness of such methods is shown to be more restricted than is often claimed. The use of certain index values to illustrate differences between taxa or affinities between them is criticized from a biological point of view. An alternative possibility of the use of variation in chromatographically obtained data is suggested. A modified analysis of variance makes it possible to study population structures and genetical systems within one taxon at a time. Variation arising from irregularities in chromatographical separation, chance, etc., can also be estimated by this method.
TAXONOMIC PLACEMENT OF THE TYPHALES WITHIN THE MONOCOTYLEDONS: PRELIMINARY SEROLOGICAL INVESTIGATION.
Authors: Lee David W. , Fairbrothers David E. 
Published: April 2006

SummaryThree types of serological precipitin techniques were employed, using seed extracts from selected monocotyledonous species and antisera to Typha and Sparganium. The obtained protein data were evaluated for use in helping to determine the placement of the Typhales within the monocotyledons. Data indicated the following: (1) significantly high serological correspondence between Typha and Sparganium, supporting the placement of these two genera within the order Typhales; (2) low serological correspondence between the Typhales and Liliales (in addition to some anomalous activity), indicating possible distant evolutionary relationships between these two orders; and (3) little or no serological correspondence between the Typhales and most of the tested monocotyledons, reflecting an isolated position for the Typhales within the monocotyledons.
THE GENERIC NAME HORNEMANNIA AND ITS DIVERSE APPLICATIONS
Authors: Stearn William T. 
Published: April 2006

SummaryThe attempts by contemporaries of J. W. Hornemann (1770‐1841) to commemorate him in the generic name Hornemannia resulted, for taxonomic and nomenclatural reasons, only in the creation of synonyms. Hornemannia Willd. (1809) was based on two species, one now referred to Mazus Lour. (1790), the other to Lindernia All. (1766). It prohibits the use of Hornemannia Vahl (1810) for a West Indian genus of Ericaceae subfam. Vaccinioideae, now to be called Symphysia C. B. Presl (1827), and of Hornemannia Benth. (1846) for an East Asiatic genus of Scrophulariaceae, now called Ellisiophyllum Maxim. (1871). Symphysia apparently comprises only one species, S. racemosa (Vahl) Stearn, first described as Hornemannia racemosa Vahl, which, being a montane little‐known plant, has been named anew from almost every West Indian island it inhabits.
CHEMOSYSTEMATIC AND NUMERICAL STUDIES OF NATURAL POPULATIONS OF JUNIPERUS ASHEI BUCH. †
Authors: Adams R. P. , Turner B. L. 
Published: April 2006

SummaryJuniperus ashei Buch. was analyzed throughout its Texas distribution for areas of population differentiation and possible hybridization with J. virginiana L. and J. pinchotii Sudw. utilizing both morphological and chemical (terpenoid) characters. The volatile terpenoids of the foliage were analyzed by gas chromatography. Numerical methods included: analysis of variance; SNK tests; contour mapping of individual characters; differential systematics; and numerical taxonomy. Some peripheral populations of J. ashei show divergence of both terpenoid and morphological characters. This divergence is not, apparently, due to hybridization with J. virginiana or J. pinchotii. No evidence of hybridization was detected between J. ashei and J. virginiana or J. pinchotii. Differential systematics and numerical taxonomy were found to be of considerable value in the analysis of infraspecific variation.
RIND AND LEAF OILS OF TRIPLOID INTERSPECIFIC CITRUS HYBRIDS AND THEIR DIPLOID AND TETRAPLOID PARENTS
Authors: Scora R. W. , Cameron J. W. , Berg J. A. 
Published: April 2006

SummaryRind and leaf oils of triploid Citrus hybrids from 5 crosses, and their diploid and tetraploid parents, were analysed by gas chromatography. Two‐thirds of the chromosome complement of each hybrid was evidently contributed by the 4n parent. Overall, a wide range of percentages of the oil components occurred among hybrids and parents. There were differences significant at 1% in 80 of 90 parent‐hybrid group comparisons. There was no regular, dominating effect of the 4n parents, and in many cases the influence of 4n and 2n parents seemed about equal. However, among hybrids involving 4n lemon there was often a tendency for leaf oil levels to follow those of that 4n parent. The general absence of such an effect in the rind oils, and in the leaf oils of the other crosses, parallels the implication of an earlier study in which autotetraploids of several Citrus species were usually similar to their parental diploids, in their percentages of rind oil components.Where 2 or 3 sets of hybrids had a common parent, either 2n or 4n, there was also no constant effect of that parent, from set to set, as compared to other parents involved. Variation in the percentages of any specific oil component was great among the 6 sister triploids in many crosses. Individuals sometimes approached the level of one parent, and sometimes that of the other. Transgression of one or more hybrids beyond either parent frequently occurred, and was particularly prominent with decanal, linalool, and linalyl acetate. Percentages of components in the leaf were often different from those in the rind.It is clear that these polyploid hybrids of rather closely related species show many inherited differences in oil components. These differences are principally quantitative and probably reflect genetic recombinations which have altered intermediate biochemical pathways.
ZUR NOMENKLATUR DER PALÄOZOISCHEN GATTUNG TRISTACHYA LILPOP 1937 (SPHENOPSIDA)
Authors: Conert Hans Joachim , Schaarschmidt Friedemann 
Published: April 2006

SummaryThe name Tristachya Lilpop 1937 for an Upper Paleozoic plant similar to Sphenophyllum is a younger homonym to Tristachya Nees von Esenbeck 1829, a living genus belonging to the Gramineae. The new name Lilpopia is proposed instead of the illegitimate name.
FLORA OF THE GUAYANA HIGHLAND: ENDEMICITY OF THE GENERIC FLORA OF THE SUMMITS OF THE VENEZUELA TEPUIS
Authors: Steyermark Julian A. 
Published: April 2006

SummaryThe summit flora of the table mountains of Venezuela would appear to be represented by a relatively small endemic generic element with an intermixture of nonendemic generic elements, originating and immigrating centripetally at different times and from different dispersals or origins (West Gondwanaland‐American, Australasian/Malaysian‐American, Australasia‐Antarctica‐American), the whole modified by evolution and differentiation on newly available areas of the table mountains during their erosional history and derivation from lowland peripheral sources during Pleistocene and post‐Pleistocene times.
ALGUNAS TENDENCIAS EVOLUTIVAS EN BURSERA (BURSERACEAE)
Authors: Rzedowski J. , Kruse H. 
Published: April 2006

ResumenSe ensaya una síntesis de los conocimientos actuales acerca de las plantas pertenecientes al género Bursera, que agrupa alrededor de un centenar de especies de érboles (o a veces arbustos) caducifolios, distribuidos mayormente en la region intertropical americana, concentréndose sobre todo en la vertiente pacífica de México.Se pasa revista a sus rasgos morfológicos més sobresalientes así como a sus afinidades ecológicas. En esta discusión se destacan: a) el carécter exfoliante de la corteza de numerosas especies de Bursera, con miras a la interpretación del significado adaptativo de tal propiedad; b) los diferentes tipos de mesocarpio ariliforme que se presentan en el género y la probable función de este órgano en la dispersión de las especies; c) dos tipos de hojas cotiledonares que se encontraron al revisar 29 especies de Bursera del Estado de Guerrero con respecto a este carécter.Sobre la base de lo anterior, se trata de interpretar las tendencias evolutivas en el género en cuanto a: 1.—hébito de la planta, 2.—características de la corteza, 3.—tipo de hoja, 4.—características del mesocarpio, 5.—afinidades ambientales.Se toca asimismo el aspecto taxonómico y el problema de las relaciones de Bursera con Boswellia y Commiphora, géneros, al parecer, estrechamente emparentados. Se propone un esquema hipotético del curso de la filogenia, en el cual se contempla la posibilidad de considerar a Bursera como un conjunto difilético.SummaryThis contribution attempts a synthesis of the present knowledge of the plants belonging to the genus Bursera, a group of ca. 100 species of deciduous trees (or sometimes shrubs), mainly distributed in American tropics and largely concentrated in the Pacific slopes of Mexico.The most outstanding morphological features of these plants are examined as well as their ecological affinities. In this discussion special emphasis is given to: a) the exfoliating bark of many species of Bursera, with the aim of interpreting its adaptive significance; b) different types of aril‐like mesocarp occuring in the genus and its probable role in the dispersal of the plants; c) two different types of cotyledonary leaves found as the result of an examination for this purpose of 29 species of Bursera in the Mexican state of Guerrero.On the basis of this discussion an interpretation of the evolutionary trends in the genus is essayed, with reference to: 1.—habit of the plant, 2.—bark characters, 3.—leaf‐type, 4.—mesocarp characters, 5.—ecological affinities.The taxonomic aspect is also approached as well as the relationships of Bursera with allied genera: Boswellia and Commiphora. A hypothetical scheme of the possible course of phylogeny is proposed, in which Bursera as a diphyletic assemblage is conjectured.
STOMATAL PATTERNS IN EMBRYOPHYTES: THEIR EVOLUTION, ONTOGENY AND INTERPRETATION
Authors: Payne Willard W. 
Published: April 2006

SummaryThe history of study and nomenclature of stomatal concepts has not yet led to full elucidation of cell pattern significance for higher plants. In this paper, a new ontogenetic system of classification is introduced that makes primary subdivision on the basis of the mode of division of the guard mother cell (GMC) with respect to the wall which cuts it from the meristemoid: diameristic, at right angles; parameristic, parallel to; and anomomeristic, without special orientation to the preceding wall. These are further subdivided on the basis of ontogeny and number of the surrounding cells. The biology of stomata is discussed as it relates to cell patterning, and fundamental ties are pointed out between stomatal configurations and epidermal ontogeny, especially with regard to whether development is rectate, proceeding in a wave from an intercalary or marginal meristem, or diffuse, proceeding with continued meristematic activity within the expanding tissue over a long period of time. The concept of perigenous stomata, those in which protodermal cells act directly as GMC's without prior division, is refuted. The primitive stoma of land plant sporophytes is interpreted to be the simplest type of diameristic, mesoperigenous stoma, in which a protodermal meristemoid divides transversely, cutting off a distal GMC which then divides longitudinally to produce the guard cells. This stoma is suggested as the progenitor type for the Angiospermae, and is the primitive type for at least the Monocotyledonae.
THE ORIGIN OF AMMANNIA × COCCINEA ROTTBOELL
Authors: Graham Shirley A. 
Published: April 2006

SummaryThe wide‐ranging, native North American species Ammannia × coccinea Rottboell (Lythraceae) is determined, on the basis of morphological and cytological evidence, to be an amphidiploid derivative (n=33) of A. auriculata Willdenow (n= 16) and A. robusta Heer & Regel (n = 17). The latter species has not been recognized in modern floras but its specific status is supported by a unique combination of floral and vegetative characters and distinctive chromosome number. Artificial backcrosses produced vigorous, but pollen‐sterile F1's confirming the suggested relationship of the species. Geographical distribution of the complex is presented.
THE STATUS OF TWO NEW ENGLAND “ENDEMIC” CARICES: CAREX ELACHYCARPA AND C. JOSSELYNII (CYPERACEAE)
Authors: Reznicek A. A. , Ball P. W. 
Published: April 2006

SummaryTwo similar species of the Stellulatae group of Carex, Carex elachycarpa and C. josselynii were considered to be endemic to the state of Maine in northern New England. Their collection history, nomenclature and unusual morphology are reviewed. Carex elachycarpa was formerly placed in the genus Kobresia due to its possession of a split perigynium. This placement is shown to be untenable on morphological grounds. Close examination showed that both these taxa are aberrant forms of other species. Carex elachycarpa was found to be more or less dioecious with long anthers and is referred to the synonymy of C. sterilis with which it shares these features. Carex josselynii was placed with the synonymy of C. echinata because of its long beak and narrow perigynia. The wider occurrence in Carex of abnormalities found in these taxa such as split perigynia is noted.
THE RELATION BETWEEN ISOZYMES AND PLOIDY LEVEL. ITS APPLICATION TO BIOGEOGRAPHICAL STUDIES OF MUSCARI ATLANTICUM (LILIACEAE)
Authors: Oliver J. L. , Rejón M. Ruiz 
Published: April 2006

SummaryIn this paper a correlation between polyploid level and esterase isozyme pattern in individuals from different Spanish populations of Muscari atlanticum has been established. We have taken advantage of this correlation to make a study of the distribution of the reported polyploid levels in 1,017 individuals from thirteen natural populations. The interest in and application of this method for bio geographical analysis are discussed.
NOMENCLATURAL NOTES ON SOME BLACK YEAST‐LIKE HYPHOMYCETES
Authors: de Hoog G. S. 
Published: April 2006

SummaryThe name of the cellar mould is discussed in the light of Article 59 of the Code. Proposals are made to replace the generic names Leptodontium and Phaeococcus by Leptodontidium and Phaeococcomyces, respectively.
CLADISTIC ANALYSIS OF COMPLEX NATURAL PRODUCTS: DEVELOPING TRANSFORMATION SERIES FROM SESQUITERPENE LACTONE DATA
Authors: Seaman Fred C. , Funk V. A. 
Published: April 2006

SummaryIn the Asteraceae, the two most taxonomically significant aspects of the sesquiterpene lactone chemistry are the patterns of skeletal and substitutional diversity. Sesquiterpene lactones can be subdivided into different classes based on their carbon skeletons. Superimposed on each skeleton is a set of substituents which collectively define a specific compound. Both skeletal classes and substitutional features display taxonomically useful patterns of distribution.A cladistic technique is demonstrated for converting these chemical features into taxonomic characters. Each character is derived via a biosynthetically based evaluation of structural diversity and determination of structural homology. Each set of homologous skeletal and substitutional characters from a taxon is arranged in a biogenetic transformation series. Outgroup comparison is used to determine the polarity of each character transformation series. The distribution of the resulting novel (apomorphic) skeletal and substitutional characters within this taxon are then used to generate a cladogram depicting the chemical synapomorphies. The chemistries of the taxa, Tetragonotheca L. and Iva L. (Asteraceae: Heliantheae), provide the two examples for the four‐step cladistic analysis. The methods employed in this analysis of sesquiterpene lactone distribution may also be applicable to other classes of complex natural products.