Black-capped and Bulwer's Petrels 117 



both very dark or sooty above. On the Pacific coast of the United States there 

 are a number of species, perhaps the most abundant being the Black-vented 

 Shearwater (P. opisthomelas] of southern California. About fourteen or fif- 

 teen inches long, it has the upper parts a uniform sooty slate, paler on the head 

 and neck, and the under tail-coverts wholly sooty grayish. According to Mr. 

 A. W. Anthony, it is extremely abundant off the coast of central California in 

 summer, and is found at all seasons of the year south of the Santa Barbara Islands. 

 It has been found breeding on San Benito Islands, all the nests being in small 

 caves, and on Natividad Island, an island some thirty-five miles south, where 

 they excavate burrows often ten feet in length. Other well-known species are 

 the Dark-bodied Shearwater (P. griseus), Townsend's Shearwater (P. auricu- 

 laris) of Clarion Island and western Mexico, and the Wedge-tailed Shearwater 

 (P. cuneatus], a species supposed previously to range from the Hawaiian Islands 

 to the Bonin Islands, south of Japan, but which Mr. Anthony has found to 

 be abundant off Lower California in May and June. Another species of wide 

 range is the Slender-billed Shearwater (P. tenuirostris] which ranges from the 

 seas about Australia and New Zealand to Alaska and Japan. It is very abun- 

 dant about New Zealand and retires inland, sometimes for fifty miles, to breed. 



Black-capped Petrel. Passing over several smaller genera, we come to 

 another large genus of Petrels (Mstrdata),t\& members of which are rather closely 

 allied to the Shearwaters, but from which they differ in having a shorter and 

 stouter bill, a very thin partition between the nostrils, relatively shorter nasal 

 tubes, and a very large "nail," which occupies at least one third the total length 

 of the lower mandible. The plumage and size in the thirty or more species is 

 very variable. They are natives mainly of the temperate and tropical portions 

 of the oceans of the Southern Hemisphere, coming northward in the Atlantic 

 casually to the British Islands and the Middle Atlantic States, and in the Pacific 

 to Alaska and Japan. One of the North American species is the Black-capped 

 Petrel (s. hasitata), a bird about fifteen inches in length, sooty brown above, 

 with the crown black and the back of the neck, upper tail-coverts, and whole 

 under surface pure white. It ranges from the West Indies to Florida and Long 

 Island, but almost nothing is known of its history or habits. Another species, 

 known as the Dark-rumped Petrel (M. phaopygia], occurs in the middle Pacific, 

 from the Hawaiian Islands to the Galapagos. Perhaps the handsomest as well 

 as the rarest species is Fisher's Petrel (JE. fisheri} of the North Pacific in the 

 vicinity of Kadiak, Alaska. It is uniform bluish gray above, the top of the head 

 white, spotted with grayish, while the cheeks, chin, throat, middle of the chest, and 

 under tail-coverts are pure white, and the lower breast, abdomen, and flanks 

 smoky lead-colored superficially, but with the feathers all pure white immediately 

 beneath the surface. It is only known from the type specimen. 



Bulwer's Petrel. The final member of this subfamily to be noticed is Bul- 

 wer's Petrel (Bulweria bulweri) of the temperate North Atlantic and Pacific 

 oceans, which differs from the last by its longer, more graduated tail, less com- 

 pressed bill, and smaller feet. It is only ten inches long and in color is uniform 

 fuliginous dusky, lighter and more grayish brown beneath, while the wings are 



