BROOKS: BIRDS FROM EAST SIBERIA AND ARCTIC ALASKA. 373: 
Mr. Dixon took several specimens at Humphrey Point during the 
early part oi June. 
One immature bird was taken at East Cape, August 29, 1914. 
LARUS RIDIBUNDUS Linné. 
A few were seen at the head of Avatcha Bay, during the second 
week of May. The collection contains a male taken at Copper Island, 
May 22,—, purchased. 
LARUS SCHISTISAGUS Stejneger. 
SLATY-BACKED GULL. 
A few were seen in Avatcha Bay during second week in May and 
about Cape Shipunski where a male was taken May 21, 1913. 
LARUS BRACHYRHYNCHUS Richardson. 
SHORT-BILLED GULL. 
Several gulls were seen on Demarcation Bay, Alaska, July 18, 1914, 
that I referred to this species. No specimens were taken. 
LARUS GLAUCESCENS Naumann. 
GLAUCOUS-WINGED GULL. 
We found this species breeding at St. Lawrence Island, and Provi- 
dence Bay, eggs taken June 20 at St. Lawrence Island being very 
advanced in incubation. 
A female taken at Copper Island, May 22, is in the purchased 
collection. i 
LARUS THAYERI, sp. nov. 
THAYER’S GULL. 
I take great pleasure in dedicating this interesting species to Col. 
John E. Thayer whose enthusiasm and generosity have greatly en- 
riched the collections of the Museum of Comparative Zodélogy. 
