388 Dr. E. Coues on Central- American Laridse. 



LARIN^. 



1. Blasipus heermanni, Bp., ex Cass. 



A very young female. It is entirely fuliginous, with no 

 signs of the white head or of the general plumbeous hue of the 

 adults. The bill flesh-coloured, its terminal third black; the 

 feet black; the worn wing-coverts, tertials, and tips of the 

 wings and tail greyish brown. 



a. Young 5, Chiapam, Pacific coast of Guatemala, January 

 1863 ; (and several other specimens in similar plumage. — 0. S.) 



2. Chroicocephalus cucullatus, Bruch, ex Licht. 



A single immature specimen, identical with the numerous 

 North American examples which have been identified with the 

 Larus cucullatus of Professor Lichtenstein by both Mr. Lawrence 

 and myself. There is an incomplete hood; the front and 

 cheeks are mostly white ; the bill and feet blackish ; none of 

 the characteristic markings of the primaries as yet apparent. 



a. Chiapam, Guatemala, January 1863. 



3. Chroicocephalus atricilla, Linu. : Coues, Proc. Acad. 

 Nat. Sc. Philad. 1862, p. 309. 



We have specimens from both coasts, — those from the Atlantic 

 in summer plumage, perfectly or partially assumed ; those from 

 Chiapam, on the Pacific, in winter or immature dress. The 

 latter have the tarsus slightly longer, and the bill somewhat 

 stronger, than the former; but these characters, showing varia- 

 tion between individuals from the same locality, are of insufficient 

 value to make any separation of the species justifiable. — 0. S. 



STERNIN.E. 



4. Thalasseus REGIUS, Gambel. 



The numerous examples of both adult and young are quite 

 identical with the common North American bird. 



a, b. Chiapam, January 1863 ; c, d. British Honduras, May 

 1862 [a. adult J ; b,c, d. immature) ; (and several other speci- 

 mens. — 0. S.) 



Haliplana fuliginosa, and Anous stolidus. These, in order to render Dr. 

 Coues's notes perfect as far as our collection is concerned, I have ventured 

 to incorporate into his paper. — O. S. 



