Abstract
LONDON. Roval Society, December 9.—Sir Archibald Geikie, K.C.B., president, in the chair.—W. J. Young: The hexosephosphate formed by yeast-juice from hexose and phos phate.—L. S. Dudgeon and H. A. F. Wilson: On the presence of hgem-agglutinins, hæm-opsonins, and hæmo-lysins in the blood obtained from infectious and non-infectious diseases in man (third report). These results are based upon some hundreds of experimental observa tions which have been made upon normal and pathological blood, and are as follows:—(1) Auto-agglutination of the red blood cells, as tested for by the methods which we have employed, may be shown to occur with specimens of pathological blood only occasionally, but never with normal blood; and auto-hsemolysis has not been met with. (2) Iso-agglutination is often met with in specimens of blood obtained from patients suffering from the same disease. (3) Hæm-agglutination is largely a specific phenomenon, both in normal and pathological blood, and the specific effect can be shown to persist even if the red cells have been subjected to high degrees of temperature or to com plete drying. (4) Hæm-agglutination and bacterial agglu tination are distinct phenomena. (5) Well-marked iso-hæmolysis in specimens of normal and pathological blood is not common, although some degree of haemolysis can frequently be demonstrated. (6) Concerning phagocytosis: It would appear necessary to avoid mixing specimens of normal or pathological blood, because just as samples of sera are known to vary in value, so do the leucocytes, although to a less extent, whether they are obtained from specimens of normal or pathological blood. Still further, by mixing samples of normal or pathological blood a hxmolytic action may be induced which in itself has been found capable of exciting abnormal results in phagocytosis. (7) It appears to be incorrect to regard a specimen of blood as normal until it has been subjected to a detailed examina tion by the methods referred to in this and the two previous communications, quite irrespective of its actual source. —L. Doncaster: Gametogenesis of the gallfly Neuroterus lenticularis (Spathegaster baccarum), part i. The cynipid Neuroterus lenticularis has two generations in the year, hatching in April and June. The April generation con sists of females only, which lay parthenogenetic eggs. Evidence is given that some of these flies lay only eggs destined to become males, other flies only eggs which become females. The June generation thus consists of males and females; the eggs are fertilised and give rise to the generation which appears in April. In the sperma-togenesis 10 chromosomes are found in the spermatogonial mitoses. In the spermatocytes, the first maturation divi sion is abortive, only a small piece of cytoplasm with the centrosome being separated. In the second spermatocyte division 10 chromosomes appear and divide equally into o the spermatids. The two spermatids are similar, except that one receives a small extra-nuclear body absent in the other. Somatic mitoses in the male show 20 chromosomes, except in the nerve-cells, which appear to contain 10 only. The eggs of the June generation undergo a double but irregular maturation division, apparently leaving 10 chromosomes in the pronucleus. Segmentation divisions in these eggs and body-cells in females of both genera tions show 20 chromosomes. The study of the matura tion of the eggs of the spring (parthenogenetic) generation is not yet complete, but suggests that the eggs of some females undergo maturation and chromosome-reduction; those of others undergo no reduction. It is suggested that the former eggs yield males, the latter females. These observations, combined with (i) those of the author on the relation between sex and a somatic character in the moth Abraxas, (2) with the inheritance of such cases as colour-blindness, and (3) with the sex-relations of “hetero-chromosomes” in insects, lead to a hypothesis as to the nature of sex. It is suggested that there are male and female sex-determinants (symbols ♂, ♀) which behave as Mendelian characters, each being allelomorphic with its absence (symbol ⊙). Females have constitution ♀ ♂ and produce ♀ eggs and ♂ eggs; males have constitution ♂ ⊙, and produce ♂ and ⊙ spermatozoa. ♀ eggs are fertilised by ♂ spermatozoa, yielding females;♂ eggs by ⊙ spermatozoa, yielding males.—Dr. E. Schuster: Preliminary note upon the cell lamination of the cerebral cortex of echidna, with an enumeration of the fibres in the cranial nerves.—Dr. F. W. Mott, Dr. E. Schuster, and Prof. W. D. Halliburton: cortical lamination and localisation in the brain of the marmoset. This research is one which has been carried out on lines similar to that previously published by two of the authors in relation to the brain of the lemur. A series of sections of the cerebral cortex has been examined in order to map out the extent and boundaries of the types of cell lamination observed. It is now well known that these differences are correlated with differences in function, and this method of histological localisation of function (as it may be termed) has been controlled by the physiological method of stimulation.—R. H. Whitehouse: The caudal fin of fishes (preliminary paper). The paper communicated is a summary of a fuller work on the caudal fin of fishes in general, but principally the Teleostei. It aims at a revision of the definitions of terms in general use, in order to disperse the vagueness surrounding these terms. Diphycercy is shown to be very vague, inasmuch as it does not specify the primary or secondary nature of the symmetry, and thus it may be dispensed with in favour of protocercy and gephyrocercy, the former of which implies primary, and the latter secondary, symmetry. Concerning heterocercy, the essential features of this condition are considered to be (1) an enlarged lower lobe, and (2) the retention of individual centra, when formed, to the end of the axis. The term “hypural” is introduced into this form, since there is evidence of these structures being formed by the union of radials and haemal arches. Under homocercy, three varieties of fin-structure are discussed for the purpose of showing (1) the breadth of the term, (2) features which determine the degree of specialisation, and (3) the taxonomic value of the caudal. Evidences of caudal abbreviation are reviewed, and a re-defining of the term “epural” is given, by which this structure is considered the dorsal homologue of the ventral hypural. The presence of radials dorsally and ventrally is directed attention to, and also the composite nature of hypurals and epurals. Finally, evidence is given in support of the theory that the per manent homocercal caudal is a shifted anal, and, moreover, support is forthcoming among the Elasmobranchs.—H, E. Arbuckle: Some experiments with the venom of Causus rhombeatus.—Vr. V. H. Veley and Dr. A. D. Waller: The comparative action of stovaine and cocaine as measured by their direct effects upon the contractivity of isolated muscle. As tested by an independent method, these two drugs are found to be of approximately equal physiological action in correspondence with their affinity values.—Sir David Bruce, Captains A. E. Hamerton, H. R. Bateman, and F. P. Mackie: Glossina palpalis as a carrier of Trypanosoma vivax in Uganda.—Prof. W. M. Hicks: A critical study of spectral series, part i., the alkalies, H and He.—G. W. C. Kaye: The distribution of the Rontgen rays from a focus bulb. A Röntgen bulb was constructed with an antikathode the inclination of which to the beam of kathode rays could be varied at will. The bulb as a whole was also capable of rotation, and thus by the use of a stationary ionisation chamber, intensity distribution curves could be obtained for the X-rays. The hardness and intensity of the Rontgen rays were found to be almost independent of the obliquity of the antikathode. Some possible improvements in the modern focus bulb are suggested in the paper.—R. D. Kleeman: The direction of motion of the electrons ejected by the α particle. When an α particle collides with a molecule, we should expect that the direction of motion of the ejected electron depends on that of the α particle. If.the whole or a part of the energy of ionisations is derived from the α particle, the electron should have a component of motion in the same direction as the direction of motion of the α particle. Some experiments to test this showed that when α particles are shot through thin metal foil more electrons are given off from the side of the foil where the α particles emerge than where they enter. This shows that the motion of the liberated electrons is on the whole in the same direction as that of the ionising a particle.—F. Soddy and A. J. Berry: Conduction of heat through rarefied gases. By the aid of the calcium absorption process of producing high vacua, the conductivity of twelve gases for heat has been determined at pressures so low that the actual path of the molecule is comparable with its mean free path (cf. Sir W. Crookes, Proc. Roy. Soc., 1880, 31, 239). By an electrical method the heat dissipated from a platinum strip, maintained at 61° in the gas, has been measured at various pressures down to a thermally perfect vacuum. As indicated by the kinetic-theory, the heat dissipated at low pressure is proportional to the pressure, whereas at higher pressures it is independent of pressure. It was found that the conductivity in the first case bore no relation to that in the second. At all ordinary pressures^ hydrogen and helium are easily the best conductors, while of the gases examined carbon dioxide was the worst. At low pressure the conductivity of acetylene, methane, and cyanogen somewhat exceeded that of hydrogen, while helium was but slightly better than carbon dioxide. At low pressures the conductivity will be defined in terms of the calories (x 10-5) dissipated per second, per 0.01 mm. of pressure, per sq. cm. of surface, per 1° difference of temperature between the surface and the wall of the con taining vessel. The symbols K and Q will be used to express respectively the experimental and calculated values of the conductivity so defined. On the assumption that the heat interchange between the molecule and the surface it impinges upon is perfect, Q is the product of the number of impacts of the molecules per second per sq. cm. and the specific heat of the molecule. By the aid of the kinetic theory, Q may readily be approximately calculated from the mean molecular velocity and the molecular heat at constant volume. In the table the gases have been arranged in ascending order of K. In the second column, which gives the relative conductivity of the gas at ordinary pressures, the figures refer to the watts dissipated by the gas in the apparatus at pressures such that conductivity was independent of pressure. In the last three columns the values of K, Q, and of the ratio of K to Q, are given.
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Societies and Academies . Nature 82, 236–240 (1909). https://doi.org/10.1038/082236a0
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DOI: https://doi.org/10.1038/082236a0