December 23, 1922J 



NA TURE 



855 



Research Items. 



Mammals and Birds from Haitian Caves. — 

 A small collection of bones of mammals and birds 

 were obtained in 1921 by Mr. J. S. Brown and Mr. 

 W. S. Burbank during geological studies under the 

 U.S. Geological Survey for the Republic of Haiti, 

 from two caves situated between 3 and 4 kilometres 

 N.E. of St. Michel and 600 metres above sea-level. 

 These bones have now been described respectively 

 by Mr. ('». S. Miller, junr., and Mr. A. Wetmore 

 (Smithsonian Miscell. Coll. vol. Ixxiv. Nos. 3 and 4). 

 Rodents were the more plentiful among the mammals, 

 the most abundant being Isolobodon portoricensis, 

 Allen, which also occurs in Porto Rico and the 

 Virgin Islands. Two new genera are established : 

 Alphaetreus, with A. montanus, n.sp., as genotype, 

 which is allied to Plagiodontia and Isolobodon ; and 

 Ithydontia, genotype i". levir, n.sp., allied to Isolo- 

 bodon. Brotomys voratus, Miller, was also present 

 as well as a ground sloth, doubtfully referred to the 

 genus Megalocuus, and a few unidentified mammals, 

 while man was represented by the head of a femur 

 and an implement made of chert. Early man, 

 however, though known to have used these rodents 

 as food, does not appear in this case to have been 

 responsible for the presence of their remains in the 

 caves. Their importation would seem to be due 

 to a huge extinct barn owl, which Mr. Wetmore 

 names Tyto ostologa, n.sp. Possibly the Chcemepelia 

 passerina, Crotophaga am, and Tolmachus gabbii, also 

 present in the caves, were further victims of the owl. 



An Indian Pond-Snail. — Dr. N. Annandale and 

 Maj. R. B. Seymour Sewell have published (Rec. 

 Ind. Mus. xxii. pp. 215-292) a memoir on the banded 

 pond - snail of India (Vivipara bengalensis). The 

 latter author contributes an account of the anatomy 

 and bionomics ; Dr. Annandale deals with the 

 systematic features and with the histology of the 

 edge of the mantle and the external ornamentation 

 of the shell. Spiral rows of horny chaetns and fine 

 spiral ridges on the periostracum are present, and, 

 indeed, best developed in the fully formed embryo, 

 and disappear, as a rule, in the full-grown shell. 

 In those shells ornamented with bands of dark 

 pigment, the latter are periostracal in origin and, 

 with the test sculpture, correspond in position with 

 the rows of chaetae and the spiral ridges. The free 

 edge of the mantle bears at least three digitiform 

 processes, — other secondary ones may be present, — 

 and the processes correspond in position with and 

 are concerned in moulding the periostracal sculpture, 

 the colour pattern and the sculpture of the test. 

 In the systematic account eleven races of the species 

 are recognised. The parasites and incolas met with are 

 recorded and include spirochastes and ciliates in the ali- 

 mentary canal, rarely sporocysts and developing cer- 

 cariae, but frequently encysted cercaria? of two species. 



Meadow Grasses. — In an article on the compara- 

 tive morphology and development of Poa pratensis, 

 Phleum pratense and Setaria italica, in the Japanese 

 Journal of Botany, vol. i. No. 2, pp. 53-85 (1922), 

 Makoto Nishimura has devoted special attention to 

 the phenomena attending the germination of these 

 grasses in comparison with Agrostis alba. In Poa 

 pratensis the percentage of germination was lowest, 

 50 per cent., and the process extended over the 

 longest time, while in Setaria 95 per cent, of the 

 seeds were viable, and started into growth very 

 rapidly. Absorbing hairs were developed on the 

 coleorhiza at an early stage, and continued functioning 

 until long after the elongation of the roots ; similar 

 hairs were also produced from the epiblast. The 

 various stages of development during the first two 

 seasons of growth have been followed out, being 

 characteristic in each case. Setaria shows the greatest 



NO. 2773, VOL. I IO] 



depth and spread of roots, but the other species 

 exhibit more branching of a larger number of extra 

 nodal roots, thus attaining the same end. Each bud 

 derived from the stool is usually associated with two 

 crown roots, in which case the bud development is 

 normal, but when only one crown root is present the 

 bud fails to grow out. In all three species the in- 

 florescence is a spike, and the embryos are of the 

 usual type. In Poa pratensis, however, polyembryony 

 is frequent, and arises in various ways, the various 

 types of abnormality apparently being due to the 

 sting of an insect. A useful bibliography and a series 

 of clear plates add to the value of this communication. 



Brazilian Meteorological Service. — Yearly 

 volumes of meteorological observations at Rio de 

 Janeiro and at numerous stations in Brazil for the 

 three years 1912, 1913, and 1914, under the super- 

 intendence of Senor Sampaio Ferraz, have recently 

 been received. Each volume contains about 100 pages 

 of tabular matter. The observations at Rio de 

 Janeiro are similar in detail to those made at 

 European observatories, hourly values being pub- 

 lished of rainfall and sunshine, and detailed monthly 

 results of general meteorological phenomena. In 

 many cases the results are compared with the mean 

 I results for more than thirty years. The observations 

 for the provinces are on a uniform scale and the 

 monthly and yearly results can be combined or 

 compared with others in different parts of the world. 

 Wind frequency is regularly recorded and also the 

 mean velocity, so that knowledge of surface winds is 

 readily available for aircraft ; the results are in 

 every way a valuable addition to the world's meteor- 

 ology. Each volume contains tables and maps 

 showing the rainfall for the first six months and 

 second six months of the year, and for the year as a 

 whole, at stations covering Brazil, the various falls 

 being shown in the maps by degrees of shading. 

 Generally the two halves of the year have very 

 different rainfalls. In each of the three years the total 

 rainfall reached 118 inches at one or more stations; 

 in 1 9 14 there were four stations with a rainfall exceed- 

 ing 118 in., the maximum being 3596 mm., or 142 in., 

 at Remate de Males, Amazonas ; this place had the 

 heaviest rainfall in two of the three years. The 

 total annual rainfall at Rio de Janeiro ranged from 

 36 to 38 inches in the three years. 



Heat Conductivities of Metals under Press- 

 ure. — Volume 15 of Contributions from the Jefferson 

 and the Cruft Laboratories of Harvard University is 

 dedicated to Prof. E. H. Hall, who for more than 

 forty years has been a member of the Harvard 

 faculty. The volume is a .reprint of 31 papers by 

 the staff and students which have appeared in 

 scientific and technical journals and proceedings 

 of societies during 1921 and 1922. Eight of these 

 papers are by Prof. Duane and his pupils and deal 

 with various properties of X-rays. Six are by Prof. 

 Bridgman, and one of these deals with high-pressure 

 experiments. The heat conductivities of eleven 

 metals have been measured up to pressures of about 

 12,000 atmospheres by the bar or by the cylinder 

 method. The rate of change with increase of pressure 

 is fairly uniform for each metal, the total change 

 for the maximum pressure being an increase for 

 lead of 21 per cent., tin 15 per cent., zinc 2-5 per cent., 

 and a decrease for iron of 0-3 per cent., copper 9 per 

 cent., silver 4 per cent., nickel 14 per cent., platinum 

 2 per cent., bismuth 38 per cent., and antimony 25 

 per cent. Between these results and those obtained 

 previously by Lussana there are serious differences. 

 The ratio of the thermal to the electrical conductivity 

 is considerably changed by pressure, a result not 

 in accord with the electron theory of conduction. 



