REVEW5 



A Study of the Structure of Feathers, ivith Reference to their 

 Taxonomic Significance. By Asa C. Chandler. University 

 of California Publications in Zoology, Vol. XIII., No. 11, 

 pp. 243-446, pis. 13-37. April 17, 1916. Published 

 separately. 



This important paj^er is divided into two parts, the first 

 deahng with the structural modifications of various kinds of 

 feathers, and the second with special group characters, modifi- 

 cations and peculiarities arranged in systematic order. 



In the first part the author discusses the occurrence, 

 distribution and structure of plumules of various kinds, of 

 filoplumes and of all the difFerent contour feathers. He then 

 proceeds to show what different modifications occur in 

 feathers of different groups of birds to produce the same 

 results so far as colour is concerned. In this connexion 

 Mr. Chandler made a very interesting discovery in the case 

 of an albino Mallard. In a normal Mallard certain parts 

 of the feathers of the violet-blue speculvim are highly modified 

 for the production of the colour. In the albino not only 

 was there no pigment, but this modification was entirely 

 lacking and the structure of the feathers of the speculum 

 was like that of normal feathers in which there is no modifica- 

 tion for colour. The factors causing pigment and specializa- 

 tion of feather structure for the production of colour would 

 thus seem to be intimately associated. 



The second part of the paper is the more important and 

 original, for no previous attempt has been made in a 

 systematic way to use differences in the minute structure 

 of feathers, as revealed by the microsco])e, as guides in the 

 classification of birds. Our present knowledge of the subject 

 is so imperfect that any additional sign-post to the true 

 relationshij^s of birds is indeed welcome. Mr. Chandler has 

 here, after enormous labour and great research, ])resented 

 us with a new guide which demands most serious consideration. 

 The author's methods of investigation seem to have been 

 very thorough. He found that so far as species of the same 

 genus were concerned, there was no considerable variation 

 in the feather structure as a rule, while generic differences 

 were usually so slight as to form no good basis. In all groups 

 higher than genera, however, he states that differences, 

 though in variable degrees, may almost always be detected, 

 though it is necessary to compare the structure of feathers 

 from the same parts of the body. 



