V f^ 3 X ] Correspondence. 93 



CORRESPONDENCE. 



{Correspondents are requested to write briefly and to the point. No attention will be 

 paid to anonymous communications?^ 



A Neglected Branch of Ornithology. 



To the Editors of the Auk : — 



Dear Sirs, — Of all the characteristics of birds, in the popular estima- 

 tion, there is probably no one which attracts more general attention than 

 their covering of feathers, and indeed it is one of the most useful distinc- 

 tions in defining the class. In view of this fact it seems strange that com- 

 paratively little has yet been published concerning the distribution of the 

 feathers on the body, and undoubtedly the majority of people still suppose 

 that feathers are as evenly distributed over the skin as is the hair of mam- 

 mals. Scientists have of course for a long time known and spoken of 

 'pteryla?' and 'apteria,' and for fifty years at least these have been not 

 uncommon terms. But since the publication in 1840, of Nitzsch's 

 'System der Pterylographie," there has been very slight advance in this 

 branch of ornithology, and the little that has been published on the 

 subject has been of a very fragmentary sort. Meanwhile the structure, 

 development and growth of feathers has received considerable attention, 

 especially of late years some important work has been done, and the 

 number, form and comparative length of both remiges and rectrices have 

 been carefully noted and much use has been made of such facts in the 

 classification of birds. The presence of crests, ruffs, plumes and excep- 

 tional feathers of every sort is always recorded, while in elaborated 

 descriptions of the larger groups, the presence or absence of an aftershaft 

 and the condition of the oil-gland is frequently mentioned. As a matter 

 of fact, however, none of these things are really concerned when we speak 

 of pterylography, for by that term is meant the arrangement in defined 

 tracts of the contour feathers, and for fifty years this interesting subject 

 has been practically neglected while all other branches of ornithology 

 have been making rapid progress. 



There are two more or less probable reasons why pterylography has 

 been so slighted. One, which seems to be the view of Professor Newton 

 in his article on 'Ornithology' in the Encyclopedia Britannica, is that the 

 work of Nitzsch is so carefully done that it is complete and leaves little if 

 anything to be added. The other reason for neglect lies in the impression 

 that there is little of practical value to be obtained from further prosecu- 

 tion of such a very technical branch of the science. If these reasons are 

 closely examined, however, it will be readily seen that neither is tenable. 

 While the work which Nitzsch did was not only very carefully done, but 

 for that time vevy exhaustively, when we consider that he was practically 

 the first to enter this new field, and so like all pioneers peculiarly liable to 

 error, the possibility that careful study will show some mistakes in his 



