BIRDS OF COLORADO. 
51 
would be supposed then that it would be not uncommon in 
Colorado and it may yet be found rarely in the western part of 
the State, or even breeding, but at present the only record for 
Colorado is the one taken by Prof. Wm. Osburn, at Loveland, 
May 7, 1890. 
54. Larus delawarensis. Ring-billed Gull. 
Summer resident, rare ; in migration, common. The only 
gull that is commonly found throughout Colorado. Many are 
seen in the spring migration and they are very common in 
autumn on all bodies of water below 9,000 feet. They migrate 
early, appearing in southern Colorado by the middle of March. 
F. M. Drew records it as breeding at 6,000 feet. (Auk, II. 
1885, II.) 
. 58. Larus atricilla. Laughing Gull. 
A gull of the South Atlantic and Gulf States accidental 
once in Colorado. One was shot at Sloan’s Lake near Denver 
in December, 1889. (H. G. Smith, Nidologist, III. 1896, 48.) 
59. Larus franklinii. Franklin’s Gull. 
Migratory; rare. Has been taken by Wm. G. Smith, at 
Loveland, and A. W. Anthony saw a freshly mounted specimen 
said to have been taken near Denver. 
60. Larus Philadelphia. Bonaparte’s Gull. 
Migratory; rare. Eight specimens have been recorded, 
and every one has been taken along the edge of the plains from 
Colorado Springs to Fort Collins. Nearly all were captured in 
the fall, when it is reported as not uncommon in some localities. 
62. Xema sabinii. Sabine’s Gull. 
Winter visitant; rare. Breeds far north and comes south 
for the winter. Five occurrences have been recorded, all in the 
fall and early winter from October to December. They were 
noted at Denver, Boulder, Loveland and Fort Collins. 
69. Sterna forsteri. Forster’s Tern. 
Summer resident, rare; in migration, not uncommon. 
According to Mr. Ridgway a few breed in the State (Bull. Essex 
Institute, V. Nov. 1873, 174), but most of them are merely 
migrants. They are almost as common in the spring as in the 
fall. They reach norlhern Colorado the last of April and early 
in May. 
71. Sterna paradisaea. Arctic Tern. 
Migratory; very rare. But two instances are on record. 
Prof. Wm. Osburn has an adult male that was shot at Loveland, 
