CHICAGO ACADEMY OF SCIENCES. 
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Bandy beach, in a small depression, about June 5tli to 10th. Very com 
men about St. Michael's. D. 
The most abundant species of large gull which is found at St. Michael's. 
B. 
181. Larus argeutatus (var) Briin. (661.) Abundant on the Upper 
Yukon, where it replaces the leucopterus of the Lower Yukon. Arrives 
before the ducks, about May 2nd. Breeds on the islands in the river, 
whence I obtained the eggs, which were laid like the other gulls, on the 
bare ground, in a slight depression. Also plentiful at Plover Bay. D. 
182. Larus borealis Brandt. (655a.) This species or variety 
connects very closely with Larus argentatus and occidentalis. With 
the wing marking of the former, the back is nearly as dark as in the 
latter. Baird. 
Not uncommon at St. Michael's, and plenty at Plover Bay, E. Siberia. 
D. 
183. Larus brachyrhynchus Rich. (664a.) Short-billed Gull. A 
river gull, abundant from Fort Yukon to the sea, but not on the sea- 
coast. Obtained by BischofF at Sitka and Kadiak. I obtained the eggs 
in abundance at the Yukon mouth, where a variety was noticed with a 
bright yellow bill. I also obtained the young gulls in downy plumage, 
near Fort Yukon. The black and white pattern on the wings varies a 
good deal ; not in itself, but in relation to the different feathers, as if it 
had been carelessly stamped on by hand with a die. The old Indians 
eat them. D. 
Abundant on the marshes and ponds up the canal or channel separat- 
ing the Island of St. Michael's from the mainland. Not so abundant on 
the open water near the Fort. B. 
184:. Chroicocephalus p/ttiafZei/j/tia B. (670.) Bonaparte's Gull. 
Not uncommon in the marshes near the Yukon, but rare on the main 
river. They are most numerous on the Kaiyuh River, not far from 
Nulato, where tliey breed. The eggs have been obtained near Fort 
Yukon ; and it is not very rare at Sitka, where Bischoff obtained speci- 
mens. D. 
185. Rissa tridactyla Bon. (672.) Kittiwake Gull. Two speci- 
mens were obtained at Sitka by BischolF. The young were shot at Aniak 
Island, north of Aliaska, by Captain Smith. They have black on each 
side of the neck. They are abundant at Sitka and Plover Bay. D. 
186. Missa brevirostris Brandt. (674.) Short -billed Kittiwake. 
This bird, occurring by thousands over a small lake on the Island of St. 
George's, is conspicuous by reason of its coral-red legs and feet, which 
would seem to indicate that this is the true form described under this 
name by Brandt. 
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