On the Tail-feutliers of the Dabchic.k. 409 



163. Larus canus Linn. Common Gull. 



Tacz. p. 1033 ; Dresser, p. 829. 



This is another species that I include upon the authority 

 of Bianchi; a specimen was obtained at Yingtzu, March 31, 

 1901. 



164). Larus veg^ Palmen. Eastern Herring-Gull. 



Tacz. p. 1028 ; Dresser, p. 834. 



a. (^ juv. Steppes, near Tsi-tsi-ha. [Sept. 1880.] 



165. PoDiciPEs CRisTATUs (Liuu.). Great Crested Grebe. 

 Tacz. p. 1251 ; Dresser, p. 877. 



Capt. Karpow procured a specimen at Yingtzu on April 4, 

 1901 (Bianchi). 



XXIII. — On the Tail-feathers of the Dabchick. 

 By W. P. Pycraft, F.Z.S., M.B.O.U. 



(Text-figure 10.) 



The following short account of the number and arrangement 

 of the tail-feathers of the Dabchick {Podicipes fiuviatUis) 

 is the result of a more minute examination of the disposition 

 of these feathers, undertaken at the request of Dr. Sclater, 

 and as a supplement to my paper on this subject published 

 in the volume of ' The Ibis ' for 1907 (p. 472). 



In that paper these feathers were described as " semi- 



plumous in character and not, apparently, exceeding 



eight in number.'^ I also pointed out that they are 

 arranged, not in a continuous series, or, after the fashion of 

 normal tail-feathers, in a close series, but, on the contrary, 

 are set in the form of a horseshoe, of which the free ends 

 are directed upwards, and so lie alternately in relation one 

 to another. 



This description is practically confirmed in detail by my 

 later work; though I still find it difficult to decide as to whether 



SER, IX. VOL. III. 2 1 



