2 20 Recent Literature. [April 



mav be possible lliat in these cases approxiinatelv similar climatir Cv^n- 

 ditions have, as Mi. Chapman states, resulted in the development of sim- 

 ilar characters, but is it not more probable that the likeness is due, at least 

 in part, to a recent genetic connection with the true Eastern forms which 

 ill their northwestern extension across the continent exist not so very far 

 to liie northward of British Columbia. There are no impassible physical 

 barriers to prevent such an origin of the birds in question, and may not 

 a connection be to some extent still kept up by the occasional infusion of 

 fresh blood of the Eastern form by means of an annual migration from 

 the northward ? 



Tiie author also mentions one or two instances where, among series 

 fairlv characteristic of the interior or of the coast forms, individuals occur 

 showing stronglv marked characters of an Eastern race. Why might not 

 this too be the result of interbreeding with a stray tnigrant from the north- 

 ward.' It is generally believed that the bulk of the 'Eastern' birds inhab- 

 iting the Mackenzie Basin and the interior of Alaska migrate southeas- 

 terly, keeping to the eastward of the Rocky Mountains. The occurrence 

 of stragj'^lers of various species southward along the Pacific coast makes 

 it seem not unreasonable that there should be a similar, though very lim- 

 ited, migration through the valleys of the interior, trifling, perhaps, in 

 numbers, vet amply sufficient to account for such facts as these. 



Following the introduction comes a formal list ip which i6o species are 

 considered in detail. '-In every instance specimens have been received 

 unless a statement is made to the contrary." Mr. Streator's field notes 

 are usually brief, but of course are of much interest, coming from regions 

 of which we have so little definite knowledge. Mr. Chapman adds in 

 many cases important, and sometimes extended, technical notes bearing 

 chiefly upon questions of geographical variation. 



Tlie paper ends with a table "giving the number of specimens of each 

 species contained in Mr. Streator's collection, and also the localities at 

 which thev were obtained," thus showing exactly upon what material 

 every conclusion of the author's is based. It would be a most desirable 

 tiling if other writers would follow this example of Mr. Chapman's The 

 table is a fitting conclusion to an excellent piece of work, one that on 

 more grounds than one takes rank as an important contribution to ornith- 

 ology.— C. F. B. 



Hagerup and Chamberlain's Birds of Greenland.* — This book, pre- 

 pared by Mr. Chamberlain from material furnished by Mr. Ilagerup, con- 

 sists of two parts. The first, an annotated list of the 'Birds of Ivigtut,' is 

 based upon a former paper by Mr. Hagerup published in the 'The Auk' 

 two years ago (Vol. VI, pp. 211-218, 291-297). This has been revised and 

 corrected, and includes the results of experience gained by Mr. Hagerup 



*The I Birds of Greenland. | By Andreas T. Hagerup. | Translated from the Dan- 

 ish ! by I Frimann B. Arngrimson. i Edited by Montasjue Chamberlain. | Bdsioh : | 

 Little, Brown, and Company. | 1891.-8^. pp. 62. 



