bluuebunny/crossref_metadata_2025_split huggingface dataset:
STUDIES ON EUROPEAN FOUL BROOD OF BEES
Authors: TARR H. L. A. 
Published: February 2008

SUMMARY“European foul brood” has been initiated in healthy nuclei by feeding either the young larvae directly or the bees naturally infected material. The disease thus produced varied from a mild transient infection to a serious form depending upon whether the inoculation had been made early or late in the brood‐rearing season. In one experiment in which a nucleus very strong in bees was employed no disease resulted.“European foul brood” has also been induced in healthy nuclei by suspending in them combs containing artificially infected larvae in which disease had been produced by feeding them pure cultures of Streptococcus apis or Bacillus alvei and then starving them under conditions favouring the growth of the bacteria. The susceptibility of nuclei to infection by this means seems to be governed by approximately the same conditions as pertain to inoculations made with material obtained from natural sources. The disease thus induced ultimately becomes a mixed bacterial infection of the brood.Attempts to cause disease by feeding the bees or larvae (without starving them) relatively large numbers of S. apis or B. alvei organisms have as yet proved unsuccessful. Whether this is due to the fact that these bacteria become attenuated with respect to virulence by culturing them on artificial media, or that decomposing brood acts as a vehicle and that the relative inoculum is greater by this method, remains to be determined.The failure to produce “European foul brood” by feeding sterile Pasteur‐Chamberland L 2 or L 3 filtrates prepared from naturally infected larvae to the bees or larvae of healthy nuclei, either with or without bacteria, may be taken as strong evidence in support of the view that a filterable virus is in no way implicated as an etiological agent in this type of disease. This conclusion is strengthened by the success which has attended the use of pure cultures of the bacteria associated with this disease employing the “starved larvae” technique described.The introduction of queen bees from nuclei affected with “European foul brood” into healthy queenless nuclei has not caused any transmission of the disease under the conditions of the experiments.Two species of S. apis Maassen have been isolated from affected larvae taken from several different cases of “European foul brood”; one of these hydrolyses both casein and gelatine, the other does not. In other respects these species appear to be identical.The etiology of so‐called “European foul brood” is discussed in detail, and it is suggested from the evidence submitted in this and other papers that it may not be a single disease with one well‐defined etiological agent, as is American foul brood, but is, perhaps, a non‐specific mixed bacterial infection of the brood of bees, especially of the brood of weak colonies. This conclusion must be regarded as temporary pending further investigation.My thanks are due to Mr D. M. T. Morland and to Mr A. Rolt, whose generous advice and assistance in connexion with the apiary work greatly facilitated the carrying out of the practical experiments.
ADELGES COOLEY1 GILLETTE (HEMIPTERA, ADELGIDAE) OF THE DOUGLAS FIR IN BRITAIN: COMPLETION OF ITS LIFE CYCLE
Authors: CAMERON A. E. 
Published: February 2008

SUMMARY

Adelges cooleyi is a pest of Sitka spruce, the primary host, and Douglas fir, the secondary host, on the latter of which it has been known in Britain since 1913.
Hitherto its life cycle in Britain has been regarded as incomplete because of the non‐viability of generation I (sexuales) on Sitka spruce and consequent absence of the subsequent generation II (fundatrix vera) and generation III (gallicolae).
Both of these generations have been discovered for the first time in Britain and their development followed.
The investigation began with the finding of the dead galls of A. cooleyi on Sitka spruce at Glen Tress in February 1935. Subsequently, dead galls were also found at Stobs, Melrose, Dreghorn and Murthly. At Melrose they were found on a new secondary host, the white spruce, Picea alba. Later the fundatrix vera of generation I was found.
The growth of the galls was followed on cut twigs in the laboratory and on growing shoots in the field; galls of the current season were found at Glen Tress, Dreghorn and Murthly.
The winged gallicolae of generation II were observed migrating to Douglas fir, where they settled and oviposited. From the eggs there hatched typical hibernating first‐instar nymphs (sistentes).
Generation III (colonici) was determined to be triple‐brooded, and this character has recently been noted in Adelges cooleyi in British Columbia.
The population of the sistentes on Douglas fir during any one winter was found to be composed of four categories, which hav* been designated.
The migration of generation IV (sexuparae) to Sitka spruce and white spruce was observed at Glen Tress and Melrose respectively. It was also verified in the laboratory.
Generation V (sexuales), for some cause or causes yet unknown, was practically exterminated during development. Only a few adults were observed. The solitary egg laid by the female of this generation was not discovered.
Further investigation is required concerning:

The causes of mortality of the sexuales.
The oviposition of the sexual female, and the sexually produced egg.
The extent of the distribution and establishment of the spruce generations in Britain.
The prospective status of A. cooleyi as a pest of Sitka spruce in Britain.

With regard to status, it would be unsafe, at the present juncture, to speculate, especially as the investigation has been conducted for only one year. I have, therefore, refrained from discussing possibilities of damage to the spruce host until more evidence is available.The writer is indebted to Mr R. Carrick, B.Sc, Research Student in the Department of Entomology, for the photograph of the winged gallicollae reproduced in PI. XXV, fig. 4. Part of the expenses incurred in conducting the investigation were met by a grant from the Earl of Moray Endowment of the University of Edinburgh, and it is a pleasure to acknowledge this assistance.
THE BIOLOGY OF THE CHRYSANTHEMUM LEAF‐MINER, PHYTOMYZA ATRICORNIS MG. (DIPTERA: AGROMYZIDE)
Authors: COHEN MORRIS 
Published: February 2008

SUMMARY

The synonymy and distribution of the chrysanthemum leaf‐miner are discussed.
The host plants are enumerated, and it is shown that the attacks on chrysanthemums decrease by August, although the flies are still common on other Compositae.
A description and comparison of the morphology of the three larval instars is given, and the method of feeding of the larva is discussed.
The puparium and emergence of the adult fly are also described, together with an attempt to separate the puparia into sexes by measurement.
Some degree of natural control is secured by the parasitism of a braconid on which a chalcid is probably hyperparasitic.
A table is included comparing the developmental period of Phytomyza atricornis Mg. and P. chrysanthemi Kowarz.
DAMAGE TO WHEAT BY HELOPHORUS NUBILUS F
Authors: PETHERBRIDGE F. R. , THOMAS I. 
Published: February 2008

SUMMARY Helophorus nubilus F. is recorded as a serious pest of wheat in East Anglia. No previous record of serious damage has been made, but slight injury was recorded iu 1922 and 1923. Observations in a number of widely separated fields show that the intensity of attack varies with the previous cropping and a serious attack occurs most frequently after rye grass and clover. The larva causes Tl most damage when the tilth is loose.Observations on the life history suggest that the species has one generation per annum. Eggs were not found, and the earliest damage to wheat was observed in January. Pupae were found in late April and early May, and adults were bred out in the laboratory at the end of May. The larval and pupal stages are described.The authors are indebted to Dr G. H. Bates and Mr J. C. Mann of the Norfolk County Agricultural Staff, and to Mr G. W. Channon, formerly of the Cambridgeshire County Agricultural Staff, who reported insect attacks on the wheat fields visited.
DAMAGE TO PANICLES OF ALOPECURUS PRATENSIS L. BY APAMEA SECALIS L
Authors: BAENES H. F. , MERCEE S. P. 
Published: February 2008

SUMMARYA brief description of the moth, and caterpillar stages of Apamea (Trachea) secalis L. is given, as well as notes on its geographical distribution, life history, host plants and economic importance. The normal damage is the withering and death of the stems of the grasses owing to the caterpillars feeding within the sheaths.An unusual type of damage is described and figured. This consists of the destruction of the flowering culms and head, exceedingly similar to that caused by the larvae of Amaurosoma flavipes and A. armiUatum. This damage has been observed over a number of years in Northern Ireland, and in 1935 at Harpenden, Hertfordshire.
A DISEASE OF CHERRY LAUREL CAUSED BY TROCHILA LAUROCERASI (DESM.) FR
Authors: GREGOR MARY J. F. 
Published: February 2008

SUMMARYA leaf spot disease of cherry laurel is described. The infected areas eventually become occluded and fall out, leaving irregular holes in the foliage. The disease is caused by Trochila Laurocerasi (Desm.) Fr., the imperfect stage of which is proved to be Gloeosporium‐phacidiellum Grove. Infection takes place on the young leaves, most commonly through wounds, and a moist atmosphere is essential for the development and spread of the disease. Control can be effected by spraying with colloidal sulphur during spring and early summer, and by cutting back the bushes only in the autumn, not at short intervals during the summer as is frequently the practice.The writer wishes to acknowledge her indebtedness to Dr G. H. Pethybridge for valuable suggestions during the course of this work, also to Dr C. E. Foister for the photographs reproduced on PL XXXI.
THE HISTOLOGY OF THE NECROTIC LESIONS INDUCED BY VIRUS DISEASES
Authors: SHEFFIELD F. M. L. 
Published: February 2008

SUMMARYAbout 12 hours after a leaf of Nicotiana glutinosa is inoculated with ancuba mosaic disease a band of necrotic material begins to form within the cell wall, usually between the lower epidermis and the spongy parenchyma. This band extends both laterally and towards the upper side of the leaf. At the same time, nuclear division is observed in the spongy parenchyma cells, but karyokinesis is not followed by cell division. As the necrotic mesh work extends the cells within it die and dry out. After about 3 days, the lesion consists of a meshwork of this necrotic material. The cells are all dead and the virus is isolated within the necrotic area, all interchange between the infected and healthy parts of the leaf having been prevented.I am indebted to Fraulein Lina Cunow for assistance in making the preparations used in this study.
A NEW APPARATUS FOR SEPARATING INSECTS AND OTHER ARTHROPODS FROM THE SOIL
Authors: LADELL W. R. S. 
Published: February 2008

SUMMARY

The published methods for the separation of insects and other animals from the soil are briefly described.
None of these methods being sufficiently rapid or efficient for soil fumigation investigations, a new method has been devised.
The principle of the method is flotation by a dense liquid (a solution of magnesium sulphate sp. gr. 1.11) aided by stirring of the soil and a stream of fine air bubbles passing from the bottom upwards through the mixture of soil and solution. This produces a froth which contains all the animals, and by raising the level of the liquid in the cylinder the froth is swept over into a tank filled with magnesium sulphate solution; here is deposited any soil that has been carried over. The clear solution is then passed on to a Buchner funnel where the insects and other animals are retained. A black filter paper is used in order to show up Collembola and other colourless organisms.
The apparatus has many advantages:

Rapidity. The separation taking 30–40 min. from taking the soil sample of 6–7 lb. weight.
Cleanliness. The operation can be carried out in an ordinary laboratory.
Efficiency. All the organisms are concentrated in a small volume of residue, less than 1 per cent of the original soil, and are undamaged.
Non‐toxicity. The great majority of the insects come through alive, so that eggs and larvae may be bred out for purposes of identification.

A full account is given of the technique employed. The solution may be used again and again as the clay settles very quickly and the clear liquid may be syphoned or poured off.
Very high figures have been obtained for the soil population. These are much in excess of those recorded by most other workers with agricultural soils; for example, from fallow land 60‐6 million animals per acre were recorded and from new grass land, 121‐4 million per acre.1
THE PROBLEM OF THE EVALUATION OF ROTENONE‐CONTAINING PLANTS II. DERRIS ELLIPTIC A, DEBRIS MALACCENSIS AND THE “SUMATRA‐TYPE” ROOTS
Authors: MARTIN J. T. , TATTERSFIELD F. 
Published: February 2008

SUMMARY

The determinations of purified rotenone, ether extract, dehydro compounds, ether‐soluble resin after potash treatment, and of the rotenone plus “deguelin concentrates” are each shown to be inadequate as a means of assessing the relative insecticidal activities of the “Sumatra‐type”, D. malacceri&is, and D. elliptica roots.
The toxicarol present in the “Sumatra‐type” derris appears to play a small but definite part in the insecticidal activity of the root.
The resin recovered from the material precipitated by potash from an ether extract of the “Sumatra‐type” root is optically active, and appears to be rich in the precursor of inactive toxicarol.
Rotenone, if present, will separate readily from a carbon tetrachloride solution of “Sumatra‐type” resin from which the toxicarol has been removed. The possibility of a standard method of rotenone determination, dependent upon suitable pretreatment of the resins, is suggested.We wish to express our indebtedness to the Copper Technical Bureau for their kindness in supplying us with samples of the “Sumatra‐type” root. We also wish to thank Dr S. Krishna of the Forestal Department of Northern India, for valuable assistance.
A DISEASE OF CULTIVATED HEATHS CAUSED BY PHYTOPHTHORA GINNAMOMI RANDS
Authors: OYLEE ENID , BEWLEY W. F. 
Published: February 2008

SUMMARY

A serious disease of the heaths Erica hyemalis, E. nivalis and E. Willmoreana has been investigated.
The causal organism was isolated and identified as Phytophthora Cinnamomi Rands.
This was shown to be capable of causing a similar disease in Antirrhinum, Calceolaria, Schizanthus and beech seedlings. It also rots apple and tomato fruits.
Infection was traced to (a) contaminated water tanks, (b) the “standing‐out” ground, and (c) plunging material.
The water tanks were cleaned by removing the debris, scrubbing with water and finally treating with formaldehyde.
The need for destroying the compost from discarded pots or alternatively of sterilizing it by heat before using it again is emphasized.
ON THE CONTROL OF GOOSEBERRY RUST
Authors: SAUNDERSON W. E. , CAIRNS H. 
Published: February 2008

SUMMARY

This investigation deals with the possibilities of controlling Aecidium Grossularia DC. (Puccinia Pringsheimiana Kleb.) on the gooseberry by means of fungicides or through the use of varieties resistant to rust.
From observations made on more than twenty varieties representative of the three types of gooseberry, red, green and yellow, no pronounced variation in resistance to the disease was found.
Very effective control of the disease resulted from spraying with fungicides: several concentrations of Bordeaux and Burgundy mixtures and proprietary colloidal preparations of copper and sulphur. Of these it is, suggested that Bordeaux mixture and the colloidal copper preparation may be recommended for general use against gooseberry rust.
The optimum time for spraying with a fungicide against rust was found to be about 2 weeks before the gooseberry commences to flower.
A single spraying gives very effective control of the disease, provided it is applied at this optimum time. Repeated spraying after this time does not appreciably increase the effectiveness of the treatment.
The results of these experiments seem to indicate that basidiospore discharge in Puccinia Pringsheimiana commences with, or soon after, the commencement of seasonal growth by the gooseberry, reaches a maximum several days before the gooseberry commences to flower and, normally, ceases some 4 or 5 weeks later.
Of the sedges present in the vicinity of the experimental centre at Galgorm, Puccinia was found on four species: Carex Goodenowii Gay., C. inflata, Huds., C. flava Linn., and C. panicea Linn. No attempt was made to correlate these with the Aecidium on the gooseberry.
THE USE OF NUMBERS OF INFECTIONS FOR COMPARING THE CONCENTRATION OF PLANT VIRUS SUSPENSIONS: DISTORTION OF THE DILUTION SERIES
Authors: BALD J. G. 
Published: February 2008

SUMMARY

A distinction is drawn between the types of infection‐dilution series given by unpurified samples of the tobacco mosaic group of viruses and viruses less resistant to loss of virulence.
Distortion of the series for the tobacco mosaic group, when inocula were diluted with distilled water or buffered near the neutral point, was shown to exist more in the concentrated than in the dilute end of the series.
An acid hydrogen‐ion concentration was found to change the form of the dilution series.
The addition of plant juices to the inocula tended to produce two opposing effects on the production of local lesions, a stimulation and a depression.
Unpurified samples of viruses less resistant to loss of virulence than the tobacco mosaic group gave low values for lesions at high dilutions.
The addition of concentrations of the order of 0.01 and 0.1 M of neutral potassium phosphate‐phthalate buffer to unpurified suspensions of X virus depressed the numbers of lesions produced.
Added in various concentrations to purified samples of X virus, the buffer produced high values for lesions at a concentration of about 0.00005 M, low values between 0.0001 and 0.001 M, a maximum between 0.001 and 0.01 M, and a decline at higher concentrations.
The presence of the buffer in inocula was shown to affect the dilution series of X virus.
A tentative hypothesis was advanced to explain the effects of salts on the production of lesions by X virus.
A BACTERIAL DISEASE OF APHIS RUMICIS LINN., APPARENTLY CAUSED BY BACILLUS LATHYRI MANNS AND TAUBENHAUS
Authors: NEEDHAM N. V. 
Published: February 2008

SUMMARYAn organism culturally resembling Bacillus lathyri Manns and Taubenhaus has been isolated from Aphis rumicis Linn. The aphides showed evidence of disease, in that they died within 24 hours of removal from the host plant. Bacteriological examination of healthy aphides indicated that they are remarkably free from bacteria; few colonies were found in cultures, even when made from the crushed insects.The writer desires to express his gratitude to Dr F. Tattersfield, of Rothamsted Experimental Station, for the provision of a normal colony of A. rumicis; to Dr Mary Barratt, of the Lister Institute, for confirmation of certain of the cultural characteristics; and to his colleagues on the staff of the Cooper Technical Bureau, who have given him helpful advice.
SOIL FUNGI AND ACTINOMYCETES IN RELATION TO MANURIAL TREATMENT, SEASON AND CROP
Authors: SINGH JAGJIWAN 
Published: February 2008

SUMMARYQuantitative

A direct correlation has been found between soil fertility as measured by crop growth, and the number of fungi and actinomycetes‐in Barnfield (permanent mangold) and Broadbalk (permanent wheat) at the Rothamsted Experimental Station.
Inconclusive or negative evidence has been obtained with regard to the phenomenon of periodicity in the fungi and actinomycetes in the soil. Evidence, on the whole, seems to suggest that numbers throughout the year scatter about a mean value with an indication of lower numbers in the winter.
No marked and dominant effect of the crop has been observed upon the numbers of fungi and actinomycetes beyond a suggestion that the wheat field, on the whole, contains a greater number of actinomycetes than Barnfield while the reverse is the case for the fungi.

Qualitative

The results do not favour the view that there exist specific soil fungus floras determined by particular manurial treatments. The more fertile plots contain, however, a greater variety of soil fungi.
In the two fields different soil forms exist in different quantities. Penicillium and forms of Dematium are more prevalent in Barnfield while Fusarium tends to predominate in Broadbalk.

Forms of Monilia occur fairly uniformly in the two fields. Species of Aspergillus and Mucor are scarce in the two fields.
A STUDY OF POLYPORUS BETULINUS (BULL.) FRIES
Authors: MACDONALD J. A. 
Published: February 2008

SUMMARY

An introductory survey is given of the distribution, synonyms, etc., of Polyporus betulinus (Bull.) Fries.
In an investigation of the parasitism of the fungus negative results were obtained from infection experiments, but field observations force the writer to the opinion that the organism is a wound parasite.
The effect of the fungus on attacked wood was traced in nature and in culture. The type of breakdown produced is regarded as a red‐brown cubical rot, attacking both sapwood and heartwood.
A study of the enzyme content of the fungus showed that it contained ferments capable of attacking lignin.
The characters of the mvcelium were investigated and the fungus is classified according to Fritz's work.
Black lines are formed in culture. They are frequently related in position to bulbils (sclerotia). It is suggested that here, as elsewhere, the hyphae of the black line may be regarded as forming the limiting layer of a resting stage of the fungus.
The fertile portion of the sporophore consists of a hymenium lining very numerous pores. The basidia form a continuous row of club‐shaped cells, interspersed with cystidia. These latter appear to be the terminal portions of fibre hyphae. The sequence of nuclear phenomena in the basidium was traced. The period of spore discharge was determined for the species and for individual sporophores.
The life of the fungus has been observed from spore to spore in culture during a space of 3 months.
Monospore cultures were obtained. The fungus is heterothallic. The spores were shown to fall into two groups when twelve monospore colonies were paired in every possible way. Monosporous mycelia have single nuclei and no clamp connexions. Mycelia which are polysporous in origin contain conjugate nuclei and bear clamp connexions.
EXPERIMENTAL SPAWN AND MUSHROOM CULTURE. I
Authors: CAYLEY DOROTHY M. 
Published: February 2008

SUMMARYThe wild grassland species Ps. campestris and Ps. arvensis show very different physiological characteristics from the cultivated varieties, and the wild haystack mushroom occupies an intermediate position, showing some of the characteristics of both.The number of spores on the basidium is correlated with these physiological differences.The two wild grassland species will not grow on stable manure compost or on any artificial medium fermented from 14 days onwards.The wild haystack mushroom also fails to grow on stable manure compost, but will tolerate the by‐products of 14 days' high‐temperature fermentation (not longer), and a compost fermented at a low temperature for 1 month.The cultivated varieties will grow on unfermented composts and also on high‐temperature composts up to 35 days, and on prolonged low‐temperature composts, but show varietal differences in the latter.A standard unfermented compost for growing spawn of all forms is described.In conclusion I wish to acknowledge my indebtedness to Dr D. A. Coult for his suggestion as to the effect of lime on the growth of the wild species; to Mr H. C. Osterstock for taking some of the photographs for the plates, and to the laboratory assistant, A. F. Emarton, for some of the photographs, and for his valuable assistance in the preparation of numerous artificial composts, and the manipulation of the large tube and battery jar cultures.