18/1.] ON NEOTROPICAL LARID^E. 575 



We have not had an opportunity of comparing L. heermanni with 

 L. crassirostris of the seas of Japan and China ; but, judging by 

 what Prof. Schlegel says (Mus. des P.-B. Lari, p. 8), it must be 

 distinct. In L. heermanni adult the bill is bright red crossed by a 

 blackish band towards the tip, and the feet are nearly black. Prof. 

 Schlegel describes the bill of L. crassirostris as yellow, and its feet 

 as yellow or greenish. 



4. Larus belcheri. 



Larus belcheri, Vig. Zool. Journ. iv. p. 358 (1829); Zool. 

 Beechey's Voy. p. 39 ; Scl. et Salv. P. Z. S. 1867, p. 991 ; Schleg. 

 Mus. des P.-B. Lari, p. 9. 



Larus f robe eni, Ph. et Land. Wiegm. Arch. 18G1, p. 292; Cat. 

 Av. Chil. p. 48. ' 



Leucophceus belcheri, Bp. Consp. ii. p. 232. 



Hab. Coast of Peru, Islay (Whitely) ; Arica (Frobeen) ; Straits 

 of Magellan (Ph. et Landb.). 



Fig. 4. 



Head of Larus helclwri (reduced one-third). 



This Gull is quite distinct from the three preceding species, with 

 all of which it has been confounded, as we have already pointed out 

 above. 



Messrs. Philippi and Landbeck have lately given an excellent 

 description of it under the name Larus frobeeni. 



The British Museum contains a fine adult specimen of this Gull, 

 obtained by Mr. Whitely at Islay ; and Salvin and Godman have an 

 immature bird with a blackish cap, from the same collector and 

 locality. 



This bird cannot, in our opinion, be associated with L. scoresbii 

 in the genus Leucopheeus, not having the short and curiously 

 wrinkled bill of that species. It stands, however, somewhat alone, 

 having the base of the bill more bare than in typical Larus (in 

 which the small frontal plumes project forward on each side of the 

 cnlmen nearly up to the nostrils), and will probably ultimately rank 

 as a distinct generic form. 



