Abstract
LONDON. Royal Society, January 28.—A. C. Seward: The Cretaceous plant-bearing rocks of Western Greenland. The paper deals briefly with the geology of the localities visited, and, more fully, with the plants collected on tBe coasts of the Nugssuak Peninsula and on the south-east coast of Disko Island. The fossils obtained include many species previously described by Heer. The Cretaceous plants are regarded as a single flora; Heer's threefold division (Kome, Atane, and Patoot series) is not accepted. Several species of ferns and gymnosperms, generally characteristic of the oldest Cretaceous floras and closely allied to Jurassic types, are found associated with representatives of Angio-sperms that are strikingly modern. The Greenland Cretaceous flora seems to be Wealden-Cenomanian in age. It is considered *that several deciduous dicotyledons were evolved in Arctic regions, where, in Cretaceous days as now, a short summer with continuous sunshine alternated with a long period of semi-darkness. From their Arctic home the flowering plants spread to the south.—W. L. Balls and H. A. Hancock: Measurements of the reversing spiral in cotton hairs. The spirals in the cell wall of cotton hairs may be dexter or sinister, and their reversals are apparently predetermined during growth in length. Genetic and ordinary environmental influences do not affect the statistical peculiarities of the reversals. The final adult length of the hair and the time taken in reaching that length do affect the reversal distribution. Nearly all the seed hairs of Gossypium begin to grow on a sinistral spiral. The angle of the helix varies around two modal values, but local variations are quite unaffected by inversion from dexter to sinister.—R. H. Burne: A contribution to the anatomy of the ductless glands and the lymphatic system of the angler fish (Lophius Piscatorius). The thymus body lies free beneath the mucous membrane of the pharynx, connected with the branchial cavity by a tube. This tube is not a duct, but more nearly resembles the crypts characteristic of the mammalian tonsil. The thyroid body is occupied by a large lymph sinus, into which lymph passes through valved openings from ventral and branchial lymphatics, and from which it is conveyed to the heart by the inferior jugular. Distributed to the mucous membrane of mouth and pharynx, and to the skin of the forepart of the body, is a system of “fine” vessels, similar in structure to small arteries. These vessels are not part cf the blood vascular system, but connect by their terminal branches with the ordinary lymphatics. They are probably an afferent system of lymphatics.—I. Gordon: The development of the calcareous test of Echinus miliaris. All elements of the permanent skeleton which are laid down in the larva are traced back to a single spherical granule. This granule, with two exceptions, becomes a triradiate spicule even in the formation of a tetraradiate spine. The exceptions are in the development of (a) the base of a typical echinoid spine where it becomes hexagonal (a modification of the triradiate symmetry), and (6) the component parts of a tooth. The development of the tetraradiate spine, the simple and the compound tube-feet discs, and the blade of a pedicellaria is new. The large buccal plates arise interradially, and there are two sets of buccal tube-feet —(a) five primary ones with simple discs; (b) five secondary ones with compound discs, which are at first ordinary ambulatory tube-feet.—F. G. Gregory and L. Batten: A critical statistical study of experimental data on the effect of minute electric currents on the growth rate of the coleoptile of barley. A statistical analysis has been made of the data on which results described by Blackman, Legg, and Gregory for the effect of electrification on the growth of the coleoptiles of barley are based. Corrected data for the controls and four electrified sets show positive results, and, taken together, provide markedly significant evidence of the physiological effect of the discharge.—H. M. Fox: Chlorocruorin: a pigment allied to haemoglobin. Chlorocruorin is a polychsete blood pigment. It is red in concentrated, green in dilute, solution. It exists in oxidised and reduced forms, having spectra analogous to oxy- and reduced hEemoglobin. The oxygen affinity is less than that of haemoglobin. Specific chlorocruorins differ in oxygen affinities; some are unsaturated at atmospheric pressure. Whereas haemoglobin and a number of related pigments all contain the same haematin nucleus, Chlorocruorin has a different hsematin. Geological Society, January 6.-W. N. Edwards: Fossil plants from the Nubian sandstone of Eastern Darfur. The plant-remains described were found by Mr. G. V. Colchester at Jebel Dirra, 75 kilometres east of El Fasher, in Darfur. They occur in highly silicified quartzitic sandstone, belonging to the Nubian Sandstone, and are the first fossils to be found in that formation in Darfur. The species identified, which probably grew in dune conditions, are Weichselia reticulata (Stokes and Webb), Frene-lopsis hoheneggeri (Ettingshausen), Dadoxylon izgyptia-cum Unger, and indeterminable fern-fragments. The beds in which they occur are thus assigned to the Lower Cretaceous, or possibly to the base of the Upper Cretaceous.-Vincent G. Glenday and John Parkinson: The geology of the Suk Hills (Kenya Colony). The Suk Hills lie in the northern part of Kenya Colony, midway between Mount Elgon and the southern half of Lake Rudolf. Sekerr, their highest point, reaches an elevation of nearly 11,000 feet. With insignificant exceptions, the rocks are of Eozoic age, and fall into two groups: a series of completely metamorphosed sediments, probably including ashes, and microcline-orthogneisses. The former group so closely resembles the Turoka series from the border of Tanganyika Territory that they cannot be separated, the whole being contemporaneous in general terms. The second group seems to be intrusive into the first.
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Societies and Academies. Nature 117, 217–219 (1926). https://doi.org/10.1038/117217a0
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DOI: https://doi.org/10.1038/117217a0