406 THE TUBE-NOSED SWIMMERS — TUBINAEES. 



According to Macgillivray, this bird has the same habit as Leach's Petrel, of 

 ejecting, when handled, a quantity of pure oil, which is carefully preserved by the 

 fowlers. This Petrel may be kept alive in confinement by smearing its breast with 

 oil, which it will suck from the feathers, drawing each feather singly through each 

 mandible. 



This Petrel is often met with far out at sea ; and will follow vessels for the sake 

 of shelter as well as for food. When the latter is thrown to them they will very 

 gracefully hover over the surface of the water with upraised wings, j>resenting very 

 much of the appearance and movements of a large butterfly hovering over a flower. 

 In this manner they pick up whatever is thrown to them, feeding on any fatty 

 substance, small crustaceans, minute fishes, and almost any refuse. 



Mr. Macgillivray thus describes the movements of these Petrels in a storm : " When 

 the waves are high and the wind fierce, it is pleasant, even midst the noise of the storm 

 and the heaving of the vessel, to watch the little creatures as they advance against 

 the gale, at the height of scarcely a foot above the surface of the water, which they 

 follow in all its undulations — mounting to the top of the wave, there quivering in 

 the blast, and making good their way by repeated strokes of their long narrow wings ; 

 then sliding down the slope, resting a moment in the advancing mass of water, 

 gliding up its side, and again meeting on its summit the force of the rude wind that 

 scatters abroad its foam-bells. I have seen them thus advancing, apparently with 

 little labor ; and in such cases less effort must be required than when they have to 

 encounter a gale before it has blown long enough to raise the waves, which afford 

 them partial shelter." 



Mr. Kobert Gray states that in the Island of Soa he found this species having its 

 holes in the soft earth. The entrances were about as large as rabbit-burrows. From 

 these, other smaller galleries branch off, so that one external aperture serves as 

 a kind of lobby for a number of pairs. 



Genus CYMOCHOREA, Cues. 



Thalassidroma, Bp. Comp. List, 1838, 64 (part; not of Vigous). 



Cymoclwrea, Coues, Pr. Ac. Nat. Sci. Philad. March, 1864, 75 (type, Procellaria leucorhoa, Vieill). 



Char. Size small, but larger than the preceding genera ; tail much more than half the wings, 

 forked, the feathers very broad at the ends ; tarsus scarcely longer than the middle toe and claw 

 (about one and a half times as long as the culmen) ; plumage dusky, with or without a white 

 rump-patch. 



The following species belong to the North American fauna, and are the only ones known : — 



4. A white rump-patch. 



1. C. leucorhoa. Uniform dusky, more fuliginous below ; upper tail-coverts white, usually 



mixed with grayish. Wing, 6.00-6.30 inches ; tail, 3.50-4.00, forked for .80-00 ; culmen, 

 .60-.65 ; tarsus, .90-.95 ; middle toe, .80-.85. Hah. Northern Atlantic and Pacific oceans. 



2. C. cryptoleucura. 1 Uniform fuliginous, the head and upper parts more slaty, greater 



wing-coverts and tertials paler, inclining to dull grayish ; remiges and rectrices dull black, 

 the latter (except middle pair) white at base ; upper tail-coverts white, the longer broadly 

 tipped with black (as in Procellaria pelagica). Bill, legs, and feet (including webs) black. 

 Wing, 5.80-6.30 inches ; tail, 3.00-3.15, forked for .20-.30 ; culmen, .00 ; tarsus, .85-.90 ; 

 middle toe (with claw), .85-.90. Hah. Sandwich Islands. 



"t 1 Cymoclwrea cryptoleucura, Ridgw. Proc. U. S. Nat. Mus.Vol. 4, 1SS2, 337 (types in Nat. Mus. I loll. ). 



