3. HALOCYPTENA MICROSOME, Coues. 



(LEAST PETREL.) 

 (Plate 3.) 



Halocyptena microsoma, Coues, Proc. Philad. Acad., 1864, pp. 79, 90 ; Baird, Brewer, 

 and Ridgway, Water Birds N. Amer., II., p. 402 (1884) ; Salvin, Cat. Birds 

 Brit. Mus., XXV., p. 346 (1896) ; Anthony, Condor, II., p. 29 (1900) ; Godman, 

 Biol. Centr.-Amer., Aves, III., p. 428 (1904). 



Procellaria microsoma, Gray, Handl. Birds, III., p. 104, No. 10,859 (1871). 



Fuliginoso-nigra, subtus paullo brunnescentior : tectricibus alarum majoribus 

 pallidioribus, cinerascenti-brunneis : cauda cuneata et albedine nulla insignis. 



The Least Petrel may be easily recognised by its small size and wedge-shaped tail. 

 The specimens in the British Museum vary somewhat in dimensions, the wing in the 

 male being 4.85 inches, and in the female from 4.75 to 5.05 inches. 



The late John Xantus first discovered this little Petrel off San Jose del Cabo, in 

 Lower California, and it has since been found breeding by Mr. A. W. Anthony on San 

 Benito Island. A single female was likewise obtained by Mr. A. Forrer off the coast of 

 Mazatlan (Biol. Centr.-Amer., Aves, III., p. 428), and Dr. C. H. Townsend records the 

 capture of a specimen which flew on board the surveying ship " Albatros," in the 

 Bay of Panama in March, 1888 (Pr. U.S. Nat. Mus., XIII., p. 141). In his account 

 of a " Night on Land in San Benito Island " (Condor, p. 28, 1900), Mr. Anthony states 

 that he found this bird on loose rocky ledges, or under stones, and on one occasion he 

 met with no less than twenty-eight of them, crowded together in a small space in a 

 wall of rock not more than seven feet wide and two high. He did not, however, observe 

 them on the other islands off the coast. He describes the cry as similar to that of 

 Oceanodroma melania and O. socorroensis, but higher pitched, and giving the idea of a 

 smaller bird; he says that the note resembled the whirring of a rapidly revolving 

 cog-wheel. 



Eggs in the British Museum, collected by Mr. Anthony, are elliptical in shape, 

 white, without any conspicuous rufous dots. Axis, 1.05 to 1.1 inch ; diam., 0.75 to 0.9. 



Adult male. Sooty-black, the under-surface slightly brown in shade, the greater 

 wing-coverts paler and ashy-brown, forming a wing-patch; quills and tail-feathers 



