bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metabolic Rate of Early vestigial and wild‐type Prepupse of Drosophila melanogaster in Relation to Genotype, Sex, and Size
Authors: Ellenby C. 
Published: August 2010

SUMMARY.

Using a manometric method, the oxygen consumption of early D. melano‐gaster prepupae was studied.
It was found that males respired faster per unit wet weight than females, that wild‐type respired faster than vestigial, and that the heterozygote did not differ from the wild‐type.
It was then noticed that the prepupae in the different groups differed in size, owing to differences in population density in the culture bottles. On modifying the culture conditions so that the prepupae were of the same size, the differences in respiration between the sexes and between vestigial and wild‐type disappeared.
It is concluded that, in early prepupae, (a) significant differences in respiratory rate between the sexes, and between the genotypes employed, are absent; (6) that body‐size has considerable influence on the respiratory rate, large animals consuming less oxygen, per mg. wet weight, than animals of smaller size. The importance of controlling the size factor in work of this type is emphasized.
On Relative Growth in Pinnotheres pisum
Authors: Williams G. , Needham A. E. 
Published: August 2010

SUMMARY.

The abdomen of the female Pea‐Crab Pinnotheres yisum shows an extremely high growth‐rate relative to that of the carapace, especially in early stages measured. That of the male shows very slight positive allometry.
There is a very shallow growth‐gradient in the male abdomen with its centre in segments V, VI. In the female the gradient is at first very steep with its centre further back, between segment VI and the telson.
The relative growth of each segment of the female abdomen shows three successive periods of simple allometry with a progressively lower relative growth‐rate.
In the second period the fall in growth‐rate is less marked in the telson than in the segments immediately in front. Finally, in the third period a definite centre of low growth‐rate appears in segment VI, where originally it was highest, the growth‐rate increasing both forwards and backwards. This encourages speculations concerning the control of growth by a centre of inhibition.“
Direct plotting of the data gives a somewhat simpler picture of growth, though careful scrutiny of the relative goodness of fit indicates that the logarithmic plotting gives a better representation of growth. This may mean that growth is determined intrinsically in the tissues themselves rather than by a general supply of “growth‐factor” from the body.
An analogy is offered to the distal movement of the growth‐centre and steepness of the gradient when relative growth of the whole organ becomes very high.
Growth during this period is largely by increase in cell‐number rather than by increase in cell‐size.
Observations on Pregnancy in the Common Bat (Pipistrellus pipistrellus)
Authors: Deanesly R. , Warwick T. 
Published: August 2010

SUMMARY.One hundred and eighty‐five common bats (Pipistrellus pipistrellus) were collected during June and July from two cottages near Clovenfords, Selkirkshire. Most of them were pregnant or lactating females, and their examination has provided fresh data on the length of gestation, the distribution of pregnancies between the two horns of the uterus, and other points of interest in connection with the reproductive cycle.
Notes on an Interspecific Pigeon Cross
Authors: J.Bond C. 
Published: August 2010

SUMMARY.The bearing of the above observations on interspecific sterility.These observations raise the question, to what extent, if any, an intersexual constitution may be resposible for the sterility observed in F. 1 hybrids in other interspecific pigeon crosses and in other species of birds.Unfortunately the importance of intersexuality as a possible cause of sterility in these Stock‐Dove Pigeon hybrids was not fully appreciated when the interbreeding was commenced in 1932.The sex‐organs of the chicks which died prematurely in the earlier years of the enquiry were not microscopically examined.If the opportunity to repeat the same cross should occur to any one interested, it is much to be desired that accurate records should be kept of (1) the sex behaviour, (2) the fertility, and (3) the constitution of the sex‐organs of the F. 1 hybrids in such a cross.In the absence of absolutely conclusive evidence of the existence of testicular tissue in the ovaries of the hybrid birds now described we must regard the question of the influence of intersexuality on sterility as at present undecided, though I think that further observations will show that such an influence does exist.In conclusion, I will mention two cases of crossbred, Br. Leg. × R.I. hens, which showed abnormal sex behaviour, and male secondary sex characters limited to the comb and wattles. In both cases the ovary contained a nodule of interstitial, but not spermatogenic testicular tissue.(C. J. Bond, Journ. Genetics, vol. xxxvi. no. 3, with references to the literature on intersexual hybrids.)
A Study of the Reproductive Cycle of the Minnow in Relation to the Environment
Authors: Bullough W. S. 
Published: August 2010

SUMMARY.

The normal reproductive cycle of the minnow, Phoxinus laevis, is described, and some environmental factors which influence it are examined.
A high temperature of 17° C. in winter allows the early maturation stages, started in the previous summer, to continue. Such development, however, only proceeds as far as the production of primary spermatocytes, or the early part of the secondary growth phase of the primary oocytes.
Long daily periods (17 hours) of artificial light in winter, together with a temperature of 17° C., induce maturation of the gonads with the formation of spermatozoa and ova. A certain critical temperature is necessary before the gonads can be stimulated to maturity.
In male fish subjected to extra light, together with a temperature of 17° C., the vas deferens is found to have acquired an opening into the kidney duct. In the female a comparable opening is not induced.
The implications of these results are examined in relation to other known types of reproductive cycles of the fish and higher vertebrates.
The Activity and Metabolism of Poikilothermal Animals in Different Latitudes.—IV.*
Authors: Wingfield C. A. 
Published: August 2010

SUMMARY.The oxygen consumption of the two British species of the polychæte worm Pectinaria has been measured for comparison with published data for an arctic species of this genus. It is shown that comparing the arctic species P. granulata and the British P. auricoma there is no metabolic adaptation to latitude, but when the former species is compared with the British P. koreni such an adaptation exists.
DESCRIPTIVE STUDY OF THE FOSSIL HEMIBHAMPHIDæ: 9. A Comparative and Descriptive Study of the fossil Hemirhamphidse from the Lower Oligocene of Chadrat (Auvergne)
Authors: PITOU Louis E. 
Published: August 2010

SummaryThe fossil fish Cobitopsis acutus (P. Gervais) of the tertiary of Auvergne, which is the object of this study, has already been described several times under different names by various authors. It has been classified also in different families. The author has redescribed it carefully from a perfect specimen in good preservation, and demonstrates its affinities and its differences with the genus Ghriodorus. For him it is an extinct form, the type of a subfamily hitherto unknown, that of Pseudochriodorinee, whose features partake both of the subfamily of the Chriodorinss and that of the Hemirhamphinse.
A NEW ENTEBOPNETJST OCCURRING IN WALES: 13. Saccoglossus cambrensis, sp. n., an Enteropneust occurring in Wales
Authors: Brambel F. W. Rogers 
Published: August 2010

SUMMARY1. The occurrence of an Enteropneust in Wales is described, and an account given of the environment.2. Saccoglossus cambrensis, sp. n., is distinguished by the following characters:‐Coloration; relative proportion of proboscis and collar; dorsal groove running the whole length of the proboscis, with a well‐marked nervous thickening beneath; large number of gill‐slits (80–90 pairs); gonads beginning a t the middle of the branchial region; absence of genital ridges; absence of projecting ridges formed by the ventral longitudinal muscle bands of the trunk; four to six concentric rings distinguishable in the arrangement of the longitudinal musculature of the proboscis; large pericardium; absence of a dorsal glomerulus; proboscis skeleton not reaching beyond the middle of the collar, and little more than half‐way round the buccal cavity; five epidermal zones in the collar; complete separation of right and left collar cavities; absence of a dorsal pouch of the buccal cavity; discontinuity between the tissues of the nerve cord and the epidermis of the collar, except at the ends; collar‐trunk septum deflected forwards to the middle of the collar; marked ciliation of the epidermis covering the ventral nerve cord in the intestinal region; shallow ventral pharynx; broad tongues, projecting more than the septa; histological details of the oesophagus; eight to twelve intestinal pores, of which the first three to five are rudimentary; simple unlobed gonads, large size of ova, and presence of yolk‐cells in the ovaries.We are greatly indebted to Professor W. M. Tattersall and to Professor C. J. van der Horst for much advice, and to the former for specimens of S. ruber. We wish to take this opportunity of expressing our thanks also to Professor J. P. Hill, F.R.S., for his advice and interest in the work; to Professor G. W. Robinson for preparing the analyses of soil given in Appendix I.; to Mr. L. H. Jackson for assistance in various ways, and to Mrs. Jackson for the drawing reproduced in PI. I.
Numerical Data on African Birds' Behaviour at the Nest: Hirundo s. smithii Leach, the Wire‐tailed Swallow
Authors: Moreau R. E. 
Published: August 2010

Summary.The data, from three nests at Amani, are derived from a total of 500 hours of observations made in spells of five hours and upwards. The effect of rain on the parent birds' activity is given in detail; rain much heavier than 1 mm. per hour reduced feeding heavily, except when termites were on the wing.Brooding of eggs and young was done only by the females; their mates helped to bring food, as a rule slightly less than half the total. Incubation period 14 days; fledging 18–21.The daily percentage of time the eggs were brooded varied from 43 to 66, with no tendency to rise at lower air‐temperatures or towards the end of the incubation periods. Frequency distribution curves are given of the duration of (a) individual spells on the eggs and (b) intervals when the eggs were left uncovered. About 70 per cent, of the spells “on” lasted 2–7 minutes and 70 per cent, of the intervals “off” 2–5 minutes. Few intervals uncovered exceeded 15 minutes and none 37. Corresponding data for the fledging period are tabulated. For the first three days the young in all the nests were brooded much as the eggs had been, but after that the amount of brooding varied greatly between the nests.After a slow rise, comparatively stable feeding rates were attained at each nest during the last week of fledging. Then the average number of feeds brought in 200 minutes varied between 75 and 97 for two young and between 49 and 65 for one. The latter, which received more meals, had the shorter fledging period. There was no well‐marked diurnal rhythm in the feeding activity except that it was usually least in the early morning. The frequency distribution of length of intervals between feeds, which naturally changed with the age of the young, is tabulated. Less than 1 per cent, of the intervals exceeded 30 minutes.
A Gynandromorph Grasshopper
Authors: Agar W. E. 
Published: August 2010

Summary.A bilateral gynandromorph of Acridopeza reticulata is described. The sexual dimorphism in this species is very marked, the male having tegmina and wings of the usual type, while the female has no wings, and the tegmina are short and crumpled. The gynandromorph has a tegmen and wing of the male type on the right side, and on the left a female tegmen and no wing. Other minor differences between the normal male and female are reproduced on the two sides. Internally, there is a testis and male accessory organs on the right side, and an ovary with its associated organs on the left. This correspondence between the gonads and the somatic sexual characters of the two sides of the body contrasts with the situation in Drosophila, where the two gonads are always of the same sex in gynandromorphs.On the usually accepted theory of the origin of this type of gynandromorph by loss of an X‐chromosome from a daughter cell during cleavage, this difference between the gynandromorphs of Drosophila and Acridopeza is in accordance with the different modes of origin of the germ‐cells in the Diptera and Orthoptera.
The Visual Responses of Flying Mosquitoes.
Authors: Kennedy John S. 
Published: August 2010

Summary.1. Observations were made on females of the yellow‐fever mosquito, Aedes (Stegomyia) wgypti, which had not had a blood meal.2. When suspended by a silk fibre they orientated inaccurately but consistently away from the source of an horizontal beam of artificial light.3. They orientated accurately towards a vertical black stripe on a white background, and would rotate maintaining this position when the stripe was rotated around them up to 25 revolutions per minute.4. Presented with two black stripes the mosquitoes faced one or other stripe, and not between the two. Light stimulation of the front part of the eye evoked a more powerful turning‐away response than stimulation of the sides.5. The mosquitoes were attracted by and followed stripes which were moving, abandoning stationary similarly striped or darker walls to do so.6. Unsuspended, freely flying mosquitoes in a wind tunnel orientated consistently up wind, keeping position or making headway as long as the background was visible, but not in darkness. Without a wind, but with transverse stripes moving along the floor, they flew with or ahead of the stripe movement, the visual equivalent of flying up wind.7. The above evidence that up wind orientation involves a visual “compensation” mechanism is discussed, and a theory of the mechanism put forward.8. The lateral ommatidia initiate the responses to light and to moving objects, working in a different way from the dorsal and ventral ommatidia, which are concerned in up wind orientation. Interplay between the two classes of response may take place.The work was carried out in the Department of Entomology of the London School of Hygiene and Tropical Medicine, during my tenure of the Avebury Studentship. I wish to thank Professor P. A. Buxton and all the members of his department, especially Dr. V. B. Wigglesworth, for their hospitality and fruitful suggestions.
Delayed Reproduction in the Spotted Salamander.
Authors: Baylis H. A. 
Published: August 2010

Summary..(1) A Spotted Salamander, kept in captivity without other salamanders, gave birth to a brood of larvae in May 1937, and another brood in April 1939. There was thus an interval of nearly two years between the broods.(2) Possible explanations of this are discussed in the light of what is known of the reproductive cycle, and possibly analogous cases in reptiles are cited.(3) It is suggested that two factors may have been involved–the retention of sperm for a longer time than usual, and an unusually prolonged gestation‐period.
The Development of Rudimentary Wings in Ptinus tectus Boield (Coleoptera: Family Ptinidse).
Authors: Waddington C. H. 
Published: August 2010

SUMMARY.The reduction of the hind wings in Ptinus tectus Boield takes place exclusively during the pupal period. It is caused primarily by the necrosis of cells throughout the whole extent of the wing epithelia; some part may also be played by a failure of the remaining cells to expand normally towards the end of the pupal period, but this is uncertain.
A Revision of some Trichomycterinæ based on material preserved in the British Museum (Natural History)
Authors: Tcheenavin Dr. V. V. 
Published: August 2010

Summary.The distinctions between the genera Scleronema Eigenmann and Trichomycterus Valenciennes can hardly be considered as of generic importance; however, the name Scleronema is retained here till further material is investigated.Three species of Scleronema are revised, Scleronema operculatum Eigenmann, Scleronema minutum (Boulenger). and Sleronema angustirostris The distinctions between the two species are apparently due to the difference in size of specimens described, but as the types of Scleronema operculatum could not be examined no conclusion on the existence of this species is made.The generic name of Hatcheria Eigenmann is considered as synonymous with Trichomycterus Valenciennes; the name of Trichomycterus areolatus Valenciennes synonymous with Trichomycterus maculatus Valenciennes; the name of Trichomycterus burmeisteri Berg synonymous with Trichomycterus macrae Girard.The change of the name of Trichomycterus Valenciennes for Pygidium Meyen, proposed by Eigenmann, is not adopted here for the reason that the name of Trichomycterus Valenciennes is a well‐established name, is not a nomen preocupatum, as Eigenmann imagined, and also as the name of Pygidium has been used by Meyen for a quite different fish which has no common features with Trichomycterus. Features used by taxonomists for the species of the genus Trichomycterus are revised.A detailed description of Trichomycterus rivulatus based on a study of 387 specimens in 62 series is given. Ten formerly described species are considered as names or synonyms of Trichomycterus rivulatus. These are:–Trichomycterus incse Valenciennes; Trichomycterus gracilis Valenciennes; Trichomycterus barbatula Valenciennes; Trichomycterus pictus Castelnau; Trichomycterus eigenmanni Boulenger; Trichomycterus pæyanus Cope; Pygidium oroyæ Eigenmann & Eigenmann; Pygidium quechuorum Steindachner; Pygidium tiraque Fowler; Pygidium atochæ Allen.The types of variation of Trichomycterus rivulatus are described and discussed.
The Elaterid Population of Mid‐ and West Wales
Authors: Jones J. R. Erichsen 
Published: August 2010

Summary.This paper is based on the examination and identification of all the larva and adult Elateridæ occurring in soil samples taken from 1871 fields in the Mid‐ and West Wales province. All the species found are listed, together with some additional species discovered by general collecting in the Aberystwyth district.The most important Elateridæ are Agriotes obscurus, A. lineatus, A. sputator and Corymbites cupreus. Athous larvæ are not particularly common, and only 15 fields were noted in which the population of Athous larvæ exceeded 100,000 per acre. In isolated instances Corymbites tessellatus, a small species of Corymbites of uncertain identity, and Cryptohypnus riparius occurred in numbers sufficient to constitute a possible danger to crops.There is little definite relation between the total Elaterid population and the altitude of the land sampled; considering the province as a whole there is an indefinite tendency for the population to rise with increase in altitude. Its composition changes with elevation, particularly in fields over 1000 ft., where the relative proportion of the population made up by the three common species of Agriotes drops from the 95·4 per cent. characteristic of lowland fields to 62·8 per cent. In such fields Agriotes is extensively replaced by species of Corymbites, particularly C. cupreus; in a high proportion of fields over 1000 ft. and in many fields with an altitude of 600–1000 ft. cupreus is probably an important pest.Of the three common species of Agriotes, obscurus is generally the most abundant and sputator the least, as far as can be gathered from records of adult beetles occurring in the soil samples. Obscurus is the dominant species at all altitudes, particularly in high ground, while sputator appears to be a lowland species, becoming rare in fields over 600 ft. and absent above 1000 ft.The average total Elaterid population for the area is 218,800 per acre. 117 fields with populations of 600,000 to 999,000 were recorded, and only 28 with populations of 1,000,000 and above. There is some evidence suggesting that with increase in the total population there is a tendency for Agriotes to form an increasing proportion of the population to the exclusion of other species, and also some evidence suggesting that fields of high population tend to be grouped together.
23. Keys to the Ethiopian Tachinidæ.—I. Phasiinæ.
Authors: Emden F. I. van 
Published: August 2010

Summary.The Ethiopian species of the Tachinid subfamily Phasiinæ sensu Mesnil are revised and keyed, the result being a reduction of the number of species and subspecies from 101 to 80, including six species described as new. Two of the latter belong to new genera.
The Corixidæ of the Faeroe Islands, with Observations on the Geo‐graphical Distribution of Corixidæ in Neighbouring parts of the World
Authors: Brown E. S. 
Published: August 2010

Summary.

Extensive collections of Corixidæ from the Faeroes have produced only Corixa carinata and C. wollastoni; it is suggested for various reasons that these are the only species which exist there. The collections have been analysed in order to investigate ecological factors which affect the fauna.
The specimens differ from British specimens of the same species in being considerably smaller, but in little else.
The sex‐ratio in the collections is surprisingly low. The adult‐nymph ratios indicate that the majority of nymphs become adult by the second half of October.
Stagnant pools produce far more Corixidæ than other types of water‐body; the composition of the Corixid fauna in these pools is dependent upon the amount of vegetation, and to a less extent upon altitude; hydrogen‐ion concentration in the islands does not vary within wide limits, and has little or no effect.
The origin of the Corixid fauna is discussed and the conclusion is reached that the two species are a relict fauna which survived the Glacial era in the islands and that they did not subsequently reach the islands by immigration.
The Corixid fauna is very limited; the paucity of species is due not to adverse climatic or other conditions existing in the islands at the present day, but to extermination during the Glacial era of any other species which may have existed before it, and their inability to re‐colonize it since by migration; this opinion is borne out by comparison with the Corixid fauna of other islands and countries.
A New Ophryoscolecid Ciliate, Entodinium insolitum, sp. n., from the Indian Rhinoceros
Authors: Watson John M. 
Published: August 2010

Summary.

An account is given of the structural features of a new ciliate, Entodinium insolitum, sp. n., from the alimentary canal of the Indian rhinoceros (Rhinoceros unicornis). It is represented by two forms, namely, E. insolitum forma insolitum and E. insolitum forma uncinatum. The material was obtained from a diarrhœic stool, but it is considered to be improbable that the presence of the ciliate was in any way responsible for the condition of the host.
The new ciliate is unique in being the first species of Entodinium to be recorded from the Perissodactyla. The possibility of cross‐infection of the rhinoceros from some other ungulate is discussed and dismissed.
The site of infection is not known, but is probably the colon or cæcum.
The resemblance and possible relationship of E. insolitum are discussed.