Mr. H. Seebohra on the Ornithology of Siberia. 163 



and in Kamchatka [Kittlitz, in Mus. Petr. fide Schrenk). 

 In spring and autumn on migration it has been found in the 

 Caspian Sea {Karelin, in Mus. Petr.) and at Ayan^ in the Sea 

 of Okotsk [Wosnessensky, in Mus. Petr.). The type of this 

 species is a skin from Greenland ; and it is described as not 

 uncommon at St. Michael's, in Alaska ; but until we have 

 evidence that it breeds on the American continent we can 

 scarcely consider it as more than an occasional visitant there. 



Larus cachinnans. Pall. 



Larus ajffinis is, par excellence, the Arctic Herring-Gull. 

 L. cachinnans might with equal propriety be called the Lake 

 Herring-Gull. It appears to confine itself during the breed- 

 ing-season to lakes, rivers, and inland seas. It is the common 

 Herring-Gull of the Mediterranean, the only species known 

 at St. Petersburg, and the only species known to breed in the 

 Caspian Sea [Rudde ^ Karelin, in Mus. Petr.) . It is found in 

 the breeding-season near the Aral Sea [Severtzoff, in Mus. 

 Petr.), Lake Saissan [Finsch ^ Brehm), S.E. Mongolia [Preje- 

 valsky, in Mus. Petr.), Lake Baical and the island of Olchon, 

 in a lake to the south-east [Radde, in Mus. Petr.) . This Gull 

 has yellow legs when fally adult, with a mantle intermediate in 

 shade between that of L. argentatus and L. affinis. Mr. Howard 

 Saunders has also pointed out to me the difference in the 

 respective lengths of the tarsus and the middle toe, including 

 the claw. In L. fuscus and L. affinis the tarsus is longer than 

 the foot, whereas in L. cachinnans and L. argentatus the con- 

 trary is the case. In L. fuscus and L. affinis it is the excep- 

 tion for the second primary to have a subterminal white spot, 

 whilst in L. cachinnans and L. argentatus it is the rule. 



In the St. -Petersburg Museum there are three skins of 

 L. occidentalis collected by Wosnessensky on the coast of 

 Southern California. This is a large form of L. fuscus, with a 

 short thick bill, very dark mantle, no wedge-shaped markings 

 on the primaries, and, as far as one can judge from dried skins, 

 very yellow legs. There is also a skin obtained by Wosnes- 

 sensky at Kodiak, on the North-American coast, which looks 

 like a skin of L. argentatus. 



rXo bo coiifinued.l 



