1887 ] PKOCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 110 



A year or two before my arrival at Beriug Island Mr. X. Grebnitzki 

 obtaiued two specimens, in the early part of spring, from the outlying- 

 islet Arij Kamen. One of these he sent to the museum at Irkutzk, where 

 it afterwards was destroyed by the great fire, while the other was pre- 

 sented to Dr. Dybowski. It is this specimen the latter alludes to when 

 he speaks of having found this species nesting on the Commander 

 Islands, a generalization which does not seem to be warranted by the 

 facts, the more so as the bird is wholly unknown to the natives. It can 

 hardly be regarded as more than an accidental visitor. ISone were seen 

 or captured during my stay. 



Curiously enough Messrs. Taczanowoski and Dybowski have dropped 

 the species altogether in their latest list. {Cf. Stejneger, Ees. Ornith. 

 Expl. Kamtsch., p. 331.) 



15 (17). Cyclorrhynchuspsittaculus (Pall.) 38. 



Common summer resident on both islands. Not observed in winter. 



16 (18). Lunda cirrhata Pall. 43. 



Breeds in great quantities on both islands, but particularly numer- 

 ous on Beriug Island. In winter, occasionally after severe gales, a few 

 specimens are found cast up on the beaches. 



17 (19). Fratercula corniculata (Naum.) 59. 



Like the foregoing, but much less numerous. 



LAROIDE^. 



18 (20). Larus glaucescens (Naum.) 02. 



A common summer resident on both islands, but particularly numer- 

 ous on Copper Island. The L. glaucus reported by Dybowski and 

 Taczanowski as observed or collected on Bering Island (B. S. Z. F. 

 1884, Extr. p. 3) may possibly be this species. 



19 (22). Larus schistisagus Stejn. 67. 



Only a few flocks observed, and one specimen shot on Bering Island 

 during the latter part of April and the beginning of May. This species 

 does not breed on the islands. 



When first describing this species (Auk, 1884, p. 231) and preparing 

 the manuscript for my "Orn. Expl. Kamtsch." (pp. 67-73), 1 had speci- 

 mens only of Larus mariuus, argentatus, cachimians, and orientalis for 

 comparison. The National Museum, since then, has received from Mr. 

 Howard Saunders three good specimens of Lams affinis Reinh., a ma- 

 terial sufficiently ample to prove beyond dispute that L. schistisagus and 

 L. affinis are entirely different. 



The fact that we have now four adult specimens, and one nearly so, of 

 L. schistisagus, all agreeing as to the essential characters, at once dis- 

 poses of the doubt expressed by Mr. Seebohm that it may be "an acci- 

 dental variety" of X. affinis (Br. B. Eggs, III, p. 324). 



In regard to size, the specimens at hand would indicate that L. schisti- 

 sagus is considerably larger than L. affinis. It should be remarked, how- 

 ever, that the only L, schistisagus, which is sexed, is a male, while two L. 



