516 Recent Literature. LOct. 



(p. 303), Moyobamba, Peru; Leucippus fallax richmondi (p. 303), Margarita 

 Isl.; Piaya cayana ceara 3 (p. 304) Ceara, Brazil; P. melanogaster ochracea 

 (p. 304) Yurimaguas, Peru; Chrysoptilus punctigula zulice (p. 305), Zulia, 

 W. Peru; Veniliornis kenionotus cearas (p. 306), Ceara, Brazil; Scapaneus 

 melanoleucus cearce (p. 306), Ceara, Brazil; and S. pollens peruviana (p. 

 307), Molinopampa, Peru. Following these is a 'Key to the South Ameri- 

 can Species and Subspecies Belonging to the Genus Piaya.' This does not 

 seem to be a very happy treatment of the subject, in-as-much-as the state- 

 ments of several authors are ignored without explanation and several 

 subspecies are omitted without any mention whatever. Thus P. c. 

 cabanisi Allen is ignored although Hellmayr states that it is a valid race 

 (Nov. Zool. XVII, No. 3, p. 401) while we find no reference to P. c. boliviano 

 Stone. We moreover look in vain for remarks "an tea" referred to at 

 bottom of p. 310. Mr. Cory's paper concludes with a 'Revision of the 

 Sparrow Hawks of South America and Adjacent Islands,' which includes 

 diagnoses of three new forms, Cerchneis sparveria andina (p. 323), Quito, 

 Ecuador; C. s. intermedia (p. 325), Villavicencio, Colombia; and C. s. 

 perplexa (p. 327), Lower Essequibo River, British Guiana, making fourteen 

 in all which are recognized by the author. — W. S. 



Burns on Periods of Incubation. 1 — Mr. Burns has done a good work 

 in compiling a list setting forth the time of incubation for some 225 species 

 and races of North American birds. Comparatively few careful studies 

 of this subject have been made, most oologists being more anxious to secure 

 the egg shells intact than to ascertain how many days will elapse before 

 the young break out of them. The figures given are therefore often esti- 

 mates or guesses rather then the result of actual observation, and some- 

 thing authoritative has been a great desideratum. The only weak point 

 in Mr. Burns' paper is that he does not quote his authority for the individual 

 figures, and the list of authors and correspondents from whose statements 

 the fist is compiled, must necessarily represent a considerable range of 

 accuracy. Even if the figures for which he could personally vouch were 

 so marked it would have added a large measure of strength to his paper, 

 as his care and accuracy are well known. The use of the query as denoting 

 "possible inaccuracy" is not clear, as we note in the case of the Sparrow 

 Hawk the period of incubation is given as " 29-30 (?) days" whereas in 

 'The Auk' for July, 1913, Miss Althea R. Sherman, in a most, careful study 

 of this species, ascertained the period from deposition to hatching in four 

 eggs of this species to be from earliest to latest 35, 31, 30 and 29 days 

 respectively. At all events Mr. Burns's list is an excellent foundation upon 

 which to build. Let there be more energy devoted to this phase of the 

 subject and less to the amassing of egg shells, and let observers check up 

 their results with Mr. Burns' list. — W. S. 



1 Comparative Periods of Deposition and Incubation of Some North American . 

 Birds. By Frank L. Burns. Wilson Bulletin, No. 90. March, 1915. pp. 275- 

 286. 



