1871.] ON NEOTROPICAL LARID.E. 579 



Not having been able to examine authentic specimens of this spe- 

 cies (from La Plata and South Brazil), we reserve our remarks on it 

 for a future occasion. If, as Bruch says, the cap of the adult bird 

 is grey like the back (J. f. Orn. 1S55, p. 288), there can be no 

 doubt of its distinctness from the brown-headed L. glaucodes. 

 Blasius and Schlegel both consider this bird identical with L. phceo- 

 cephalus, Sw., of the coast of Africa. 



As regards Larus maculipennis of Lichtenstein, Blasius is of opi- 

 nion that it is a distinct species, allied to L. glaucodes*. But L. 

 maculipennis of Burmeister certainly belongs to the present bird. 



Genus 2. Leucoph.eus, Bp. 

 1. Leucophceus scoresbii. 



Larus scoresbii, Trail, Mem. Wern. Soc. iv. p. 514 (1823) ; Pelz. 

 Orn. Novara Exp. p. 151; Abbott, Ibis, 1861, p. 165; Sclater, 

 P. Z. S. 1860, p. 391. 



Larus hcematorhynchus, King, Zool. Journ. iv. p. 103 (1828); 

 Jard. et Selb. 111. Orn. t. 106; Darwin, Zool. Beagle, hi. p. 142; 

 Ph. et Landb. Cat. Av. Chil. p. 48. 



Leucophceus hcematorhynchus, Bruch, J. f. Orn. 1853, p. 108, et 

 1855, p. 287. 



Leucophceus scoresbii, Blasius, J. f. Orn. 1865, p. 378. 



Hab. Patagonia, Port St. Julian (Darwin) ; Falkland Islands 

 {Abbott) ; Chiloe [Ph. et Landb.). 



This Gull is easily recognizable in every state of plumage by the 

 peculiar form of the bill, which fully entitles it to generic rank. 

 The young bird has a brown cap, just as in Larus belcheri, which 

 disappears in the adult. 



Fig. 5. 



Head of Leucophceus scoresbii (reduced one-third). 



Subfam. IV. Lestridin^e. 

 Genus Lestris, 111. 

 1. Lestris antarcticus. 

 Lestris antarcticus, Less. Trait. d'Orn. p. 606 (1831); Abbott, 



* Journ. f. Orn. 18(55, p. 374. 



