I02 Recent Literature. \a^ 



The number of species treated in the present volume is 221, with 168 

 additional subspecies, or a total of 3S9 forms, of which about one half 

 come within the scope of the A. O. U. Check-List, the rest being extra- 

 limital. In preparing the present volume the author has had far more 

 material, and given a far greater amoimt of time to the subject than any 

 of his predecessors, and in justice to him it is but fair to give here his own 

 statement of how the investigation has been conducted: "No doubt many 

 of the forms which the author has recognized'as subspecies in the present 

 work may appear trivial to others, especially those who have not had 

 advantage of the material upon which they are based; but in all cases it 

 has been the author's desire to express exactly the facts as they appear to 

 him in the light of the evidence examined, without any regard whatever 

 to preconceived ideas, either of his own or of others, and without consid- 

 eration of the inconvenience which may result to those who are inclined 

 to resent innovations, forgetful of the fact that knowledge can not be 

 complete until all is known." Yet it is sometimes possible for slight 

 differences to become magnified and their importance over-estimated by 

 long and intense consideration of them — in other words, there is danger 

 of losing one's poise of judgment in dwelling upon minute details, which 

 tend thereby to assume exaggerated importance. 



In comparing the present work with the A. O. U. Check-List, so far as 

 they cover the same field, it is to be noticed that in a few instances forms 

 admitted by the A. O. U. Committee have been rejected by Mr. Ridgwa_y, 

 while on the other hand a larger number that have been rejected, or held 

 in abeyance by the Committee, are here recognized. Probably neither 

 can be assumed to be always in the right, and that in some cases the last 

 word has yet to be said. 



The volume bears on every page the stamp of patient and conscientious 

 labor and that thoroughness of research which characterizes all its author's 

 work. When the ' Birds of North and Middle America ' is completed we 

 shall have for the first time a treatise including the whole North 

 American avifauna down to the Isthmus of Panama, together with that 

 of the West Indies and the Galapagos Archipelago, for which students 

 of ornithology the world over cannot be too grateful. It is to be hoped 

 that strength and health will enable the author to complete the herculean 

 task already so well advanced. — J. A. A. 



Scott on the Song of Baltimore Orioles in Captivity. 1 — The observa- 

 tions here detailed are of remarkable interest as tending to throw light on 

 the question of how birds acquire their distinctive songs and call notes. 

 It is, indeed, not too much to say that this is one of the most interesting 

 and important series of observations as yet contributed to the subject. 



' Data on Song in Birds. Observations on the Song of Baltimore Orioles 

 in Captivity. By William E. D. Scott. Science, N. S., Vol. XIV, No. 353, pp. 

 522-526, Oct. 4, 1 90 1. 



