326 



NATURE 



[June 15, 1916 



"Oil-seeds and Feeding-Cakes" (London: John Mur- 

 ray, 1916), and need not be repeated here. The action 

 taken was so successful that when the Oilseeds Com- 

 mittee began its investigations in June, 1915, it was 

 in the fortunate position of merely having to con- 

 solidate an industry instead of having to create one. 

 Full justice is done in the report to the work of the 

 Imperial Institute, the British agricultural colleges, 

 and the Board of Agriculture, all of which took part 

 in the scientific, technical, and commercial investiga- 

 tions which led to this successful result. The Com- 

 mittee makes four recommendations with a view to 

 the retention of the new industry in British hands 

 after the war, and of these two are to be put into 

 immediate action, in accordance with instructions 

 contained in a despatch from Mr. Bonar Law 

 to the Governments of Nigeria, Gold Coast, and 

 Sierra Leone, printed with the report. The first of 

 these is the imposition of an export duty of 2Z. per 

 ton, or more if necessary, on all palm kernels exported 

 from West Africa to ports outside the British Empire. 

 The second recommendation is that the West African 

 Departments of Agriculture and Forestry should take 

 measures to continue and extend their investigations 

 of the oil palm, and that "these measures should be 

 taken in co-operation on the scientific and technical 

 side with the Imperial Institute, by which admirable 

 work has been done In the past in connection with the 

 oil palm, and to which much of the existing know- 

 ledge of the palm and its economic products is due." 



The care expended on the well-being of the animals 

 in modern zoological gardens is well illustrated in the 

 forty-fourth annual report of the Zoological Society of 

 Philadelphia, which we have just received. As in the 

 Gardens of the Zoological Society of London, the most 

 searching post-mortem examination is instituted in the 

 case of every death, and as a result discoveries are 

 made the importance of which is not to be measured 

 by their immediate value to the society concerned. In 

 the present report the most interesting items are a 

 mysterious epizootic among the waterfowl, and of an 

 arachnoid parasite in the lungs of monkeys. The 

 lesions they produce simulate, and may be mistaken 

 for, tubercles. But their presence does not seem seri- 

 ously to affect the host. The original habitat and 

 mode of transmission are unknown, but no fewer than 

 four different species have been described, and have 

 been taken from monkeys both in India and Africa, 

 as well as from captive specimens. 



Dead bodies of the short-tailed petrel, to the number 

 of many hundreds, have periodically been found along 

 the beach at UUaduUa, New South Wales, and a like 

 mortality prevails on some islands a few miles off the 

 mainland. Naturally such discoveries have given rise 

 to much speculation among ornithologists. As a rule 

 it is attributed to disease, starvation, or storms. But 

 Mr. G. Basset Hull, in the Emu for April, advances 

 what seems to be a much more probable explanation — 

 to wit, that these are the victims of the struggle for 

 breeding territory with the larger and more powerful 

 wedge-tailed petrel. Support is lent to this view from 

 the fact that on one island, where the wedge-tailed 

 species were breeding in large numbers, no burrows 

 were found tenanted by the short-tailed species, but 

 their dead bodies were found outside the burrows of 

 their larger rivals. If, indeed, the smaller species 

 is harried, buffeted, and finally driven off in an ex- 

 hausted state by the larger, then the struggle for exist- 

 ence in the case of the short-tailed petrel must be 

 indeed severe. It is to be hoped that an attempt will 

 be made to set this matter at rest, for it raises a point 

 of quite exceptional interest. 



NO. 2433, VOL. 97]' 



In the Australian Zoologist (vol. i., part 3) Dr. A. S. 

 Le Souef, the director of the Zoological Gardens, 

 Sydney, records some interesting colour variations of 

 opossums of the genus Trichosurus. The general 

 coloration of the common opossum {Trichosurus vul- 

 pecula) is grey above, whitish below. The variants on 

 this are rufous, black, and fawn, but it seems difficult 

 to associate such variations with environmental con- 

 ditions. Thus " brown " coloured individuals are most 

 common in Tasmania, and appear to be confined 

 to the moist, heavily timbered districts ; but on the 

 mainland brown-coloured specimens are very common, 

 "particularly in the drier districts." The descendants 

 of the Tasmanian opossum turned out at Lyttelton, 

 New Zealand, some five and twenty years ago already 

 show variation from the typical form, since the animals 

 have become darker and the fur longer and less dense. 

 The author suggests that Mr. Oldfield Thomas, of the 

 British Museum, was in error when he described the 

 mountain opossum (T. caninus) as brown in colour. 

 This hue appears only in the black opossum after it 

 has been partially depigmented by immersion in 

 spirits. The existence of the black opossum is here 

 recognised for the first time, being designated a dis- 

 tinct subspecies (T. caninus nigrans). This well- 

 marked subspecies " is found in the heav\- coastal 

 scrubs in north-eastern New South Wales and 

 southern Queensland." 



In the report of the South African Museum for 

 1915, just issued, Dr. L. Peringuey, the director, re- 

 lates a very extraordinary occurrence. While the 

 troops of the Union were camped in the wide sand- 

 belt of Luderitzbucht and Swakopmund, waiting to 

 advance inland, there appeared, suddenly, after heavy 

 rains — a thing almost unheard of in those parts — all 

 along the line, immense swarms of moths. The fact 

 is the more extraordinary and mysterious since these 

 sands are almost void of visible vegetation. That 

 they were brought by the wind from inland Dr. 

 P^riguey considers improbable. They disappeared as 

 rapidly as they came. Samples which were sent to 

 the museum proved to consist of no fewer than twenty 

 species of Noctuidae. In this report mention is also 

 made of the fossilised skull of the " Bosk op " man 

 found in the Transvaal, and of fragments of limb- 

 bones, probably of the same skeleton. This skull, 

 which seems to be remarkable for its great length, has 

 not yet been described in detail. It is much to be 

 hoped that this will soon be done. A mandible found 

 in the river-gravels at Harrismith, in the Orange Free 

 State, and stone implements found in another locality 

 in the Orange Free State, are also mentioned among 

 the acquisitions for the year deserving special men- 

 tion. 



In an article under the title "The Reflex as a 

 Creative Act" (Bull. Imp. Acad. Sci., Petrograd, 

 November, 1915), the eminent Russian biologist S. I. 

 Metalnikov discusses the nature of reflex action, and 

 contests the position of those biologists and physio- 

 logists who maintain (a) that reflex action pre- 

 supposes the existence of a central nervous system ; 

 (b) that reflexes are unconscious and involuntary; (c) 

 that they are uniform and invariable. If, he says, 

 we concede these premises we are at the outset 

 brought up against a whole series of difficulties. In 

 many of the lower Invertebrata, and in all unicellular 

 organisms, the most careful research fails to reveal 

 any central nerves, yet they react to various stimuli 

 no less than the higher organisms. Further, we can 

 never determine by direct observation whether a re- 

 action is voluntary or involuntary. And, lastly, even 

 as no two organisms are exactly alike, so there are no 



