318 BIRDS OF WESTERN AND 



307. Sterna maxima Bodd. 



Mazatlan, Bischoff; Isabella Island, Grayson; Guayamas, Dr. Palmer. 



A few of this species are seen in the summer months, but like S. elegans, they congregate into flocks in 

 March, and soon depart for their breeding places." 



308. Sterna forsteri Nutt. 

 Mazatlan, Grayson. 



" This species is quite abundant along the shores and esteros from October until April." 



309. Sterna superdliaris VieiU. 

 Manzanilla, Xantus. 



310. Maliplana fuUginosa var. crissalis Baird. 



" " Proc. Bost. Soc. of N. H., xiv., pp. 285, 301. 



Tres Marias, Socorro, Grayson. 



311. Hydrochelidon fissipes (Linn.). 

 Mazatlan, Grayson. 



"Makes its appearance in this locality in September and October ; remains all the winter months." 



312. Anous stolidus (Linn.). 

 Isabella Island, Grayson. 



" I found this species breeding in communities on the north end of the island, upon shelving rocks, beneath 

 the overhanging cliffs, like mud swallows. There were a great many of them in this one particular locality, 

 and when fired at they came down in swarms over the canoe, and circled around like swallows. The nests 

 were placed close together, but inaccessible. I, however, managed to procure one egg ; it is white, with scat- 

 tering brownish blotches, more numerous on the larger end, and is oval in shape. I believe but one egg is 

 found in each nest." 



313. Mhynchops nigra Linn. 



San Bias, Grayson; Zacatula River, Xantus. 



" I have observed this species during the summer months, especially near San Bias. It is not numerous, 

 and partly nocturnal." 



Fam. Peocellaeid^. 



There are no specimens of this family in any of the collections from Western Mexico ; 

 but two are named in Col. Grayson's list, viz. : 



" Stormy Petrel (White rump)." 

 "Dusky Petrel — very common." 



Their determination can only be arrived at by examples. 



Fam. CoLTMBiD^. 



One species of this family is on Col. Grayson's list, from the Island of Isabella, viz. : 

 " Guillemot." There being no specimen it cannot be determined. 



