Recently published Ornithulogical Works. 349 



characters, as may be gathered from his arguments (on 

 page 7) that " fluctuating variations " brought about l)y 

 environment are due to differences of vigour. Vigour, 

 he says, affects the offspring and we thus get supei'imposed 

 on tlie mendelian characters an heredity brought about hy 

 environment (italics ours). 



Ornithologists can hardly fail to be interested in the 

 many illustrations given by Mr. Bonhote in which he strives 

 to show that temperature, humidity and food-supply influence 

 vigour and through vigour coloration. In his discussions 

 on the subject of coloration, however, Mr. Bonhote appears 

 to us to hardly do more than touch on the fringe of the 

 subject, for he draws no distinction between coloration 

 or mere depth of tones or shades and colour-pattein. 

 Differences in colour-pattern cannot, we conceive, be 

 caused by either temperature, humidity, food-supply, or 

 any amount of vigour. 



In our belief there are " environmental or physiological 

 species " and " germinal species " — the last perhaps the 

 only true species. Mr. Bonhote does not appear in his 

 book to distinguish sufficiently between the two. All his 

 arguments seem to us to apply to the former category. 

 To our mind the most interesting chapter in the book is 

 that on '' The Evolution of Sex/' 



Chapman on new Colombian Birds. 



[Diagnoses of apparently new Colombian Birds. — IV. By Frank M. 

 Chapman. Bull. Amer, Mus. Nat. Hist. New York, xxxiv. 1915, 

 pp. 635-662.] 



The already large collections of birds from the northern 

 parts of South America in the American Museum have 

 recently been further enriched by a visit of the collectors, 

 Messrs. Miller and Boyle, to the parts of the province of 

 Antioquia hitherto not explored by naturalists. In the 

 present paper a number of new forms collected by them as 

 well as by others are diagnosed. 



Only one new species is described — Crypturus kerrite. 

 Twenty-four new subspecies (belonging to the genera 

 Crypturus, Tachytriorchis, Herpetothei'es, Aulucorhynchus, 



