226 WILSON'S PETREL. 



caught, they squirt an oily substance through the nostrils, and often disgorge 

 the same. The sexes are similar in their external appearance. 



Stormy Petrel, Procellaria pelagica, Wils. Amer. Orn., vol. vii. p. 90. 

 Thalassidroma Wilsonii, Bonap. Syn. ; p. 367. 

 Wilson's Stormy Petrel, Nutt. Man., vol. ii. p. 322. 



Wilson's Petrel, Thalassidroma Wilsonii, Aud. Orn. Biog., vol. iii. p. 486; vol. v. 

 p. 645. 



Male, 7i, 15§. 



Wanders from the Gulf of Mexico, off the whole Atlantic coast to Baffin's 

 Bay, and often almost across the ocean towards Europe. Breeds in vast 

 numbers from Maine to Baffin's Bay. 



Adult Male. 



Bill shorter than the head, slender, straight, with the tips curved, as* broad 

 as high at the base, compressed towards the end. Upper mandible with the 

 nostrils forming a tube at the base, beyond which, for a short space, the 

 dorsal line is straight, then decurved, the ridge narrow and separated from 

 the sides by a narrow groove, the edges sharp, inflected, the tip compressed, 

 obliquely deflected. Lower mandible with the angle rather long, narrow 

 and pointed, the dorsal line beyond it very slightly concave and decurved, 

 the sides erect, the edges sharp, the dip slightly decurved. 



Head of moderate size, roundish, anteriorly narrowed. Neck short. 

 Body rather slender. Feet long, very slender; tibia bare at its lower part; 

 tarsus very slender, reticulate, anteriorly with a long plate which is very 

 slightly marked. Hind toe conical, so minute as scarcely to be perceptible; 

 anterior toes rather long and extremely slender, obscurely scutellate above, 

 connected by striated webs with concave margins; the third and fourth toes 

 longest, and about equal. Claws slender, arched, depressed, acute. 



Plumage very soft, blended, the feathers distinct only on the wings, which 

 are very long; primary quills tapering, but rounded, the third longest, the 

 second slightly longer than the fourth, the first much shorter and a little 

 longer than the sixth; secondaries short, the outer incurved, obliquely 

 rounded. Tail rather long, even, of twelve broad rounded feathers. 



Bill and feet black, but the webs yellow excepting at the margin. Iris 

 dark brown. The general colour of the plumage is dark greyish-brown, the 

 quills and tailbrownish-black, the outer secondary wing-coverts and some of 

 the secondary quills light greyish-brown, and tipped with whitish. The 

 rump, sides of the abdomen, and exterior lower tail-coverts, white. 



Length to end of tail H inches, to end of wings 8, to end of claws 8; 

 extent of wings 15|; wing from flexure 6; tail 3f-; bill along the back T 7 2, 



