June 20, 1919] 



SCIENCE 



593 



scarlet tanagers and bobolinks under careful 

 obseiration. Little by little the supply of 

 light was cut off and the amount of food was 

 increased. In about a month, when tlie time 

 for the normal autumn moult arrived, the 

 tanagers and bobolinks were living the " sim- 

 ple life " in a dim illumination, and, although 

 consiuning a fair amount of food, were exer- 

 cising but little. As the winter gradually 

 passed, it was evident that the birds had 

 skipped the autumn mouJt entirely and ap- 

 peared to suffer no inconvenience as a resvQt. 

 In the following spring individual tanagers 

 and bobolinks were gradually brought under 

 normal conditions and into their seasonal 

 activities, with quick result. The birds 

 moulted into the colors appropriate to the sea- 

 son ; there was no exception ; the moult was 

 from nuptial to nuptial, not from nuptial to 

 winter plimiage; the dull colors of the winter 

 season had been completely suppressed. Of 

 an entirely different character is Beebe's sec- 

 ond paper, " A Contribution to the Ecology 

 of the Adult Hoatzin," a bird which presents 

 a most remarkable survival both of habit and 

 structure in the presence of claws on its wing 

 phalanges and in its tree-climbing habits. 



Interspersed with the biological papers are 

 some which are partly biological and partly 

 systematic, such as Beebe's third paper, " An 

 Ornithological Reconnaissance of Northeast- 

 em Venezuela." It was learned in the zoolog- 

 ical researches of Venezuela and in the more 

 recent work in British Guiana, at the Tropical 

 Research Station, that a systematic survey of 

 the zoology and botany of any region is abso- 

 lutely essential for broad and intensive bio- 

 logical and experimental work. Thus there 

 also appear in this volume the first series of 

 systematic papers on the " Insects of British 

 Guiana," by Kellogg, Caudell and Dyar; also 

 " Notes on Costa Eican Birds," by Crandall. 

 These will be followed in Volume II. of 

 Zoologica by very complete check-lists of the 

 birds and mammals of British Guiana, to 

 which the Zoological Society observers have 

 made verj- extensive additions. 



Of more general zoological character of the 

 older kind are Townsend's observations on the 



" Northern Elephant Seal," describing his 

 discovery of a previously unknown herd on 

 Guadalupe, an uninhabited island lying in the 

 Pacific Ocean 140 miles off the northern part 

 of the peninsula of Lower California. There 

 is also a series of morphological papers, such 

 as those of Beebe, on the " Supernumerary 

 Toes in Hawks," and of Gudger, on " The 

 Whale Shark." One pathological paper has 

 found its way into this volimie. namely, that 

 of W. Reid Blair, entitled. " Common Affec- 

 tions among Primates." Other papers of this 

 character, however, will be placed in the spe- 

 cial pathological series to be issued by the 

 Zoological Society. It is not intended to con- 

 tinue in these volumes of Zoologica such 

 papers as MacCallum's " Ectoparasitic Trema- 

 todes," not because they are not of interest 

 and value, but because they belong more 

 properly with other series of researches. 



Quite germane to this volume, however, are 

 Ditmar's observations on the " Feeding Habits 

 of Serpents," and Beebe's careful studies on 

 the '■ Racket Formation in Tail-Feathers of 

 the Motmots." which describe the rare phe- 

 nomenon of the apparent voluntary mutilation 

 of plumage of birds with its well known bear- 

 ing on Lamarckism. We have known abso- 

 . lutely nothing of the actual cause of this phe- 

 nomenon ; either how it arose, why it is so 

 persistent, or what good is accomplished. For 

 some reason totally unknown to us a certain 

 portion of the central rectrices of these birds 

 exhibits congenitally a decided degeneration 

 of the barbs and barbules; the motmot, in the 

 course of the preening to which it subjects all 

 of its rectrices, breaks off the enfeebled barbs 

 in the area most affected by this degeneration, 

 and thus brings about the remarkable, symmet- 

 rically formed rackets. Thus an apparently 

 purposive act is explained as being due to the 

 weakness or hereditary degeneration in a cer- 

 tain portion of the tail. 



The Zoological Society thus puts forth its 

 first volume of collected contributions by 

 younger men who have been trained chiefly 

 within its staff and by its expeditions on land 

 and sea, in the hope of striking the new and 

 inspiring note which normal life always gives. 



