PETRELS AND ALLIED SPECIES. 425 



contrary, very small, and usually reversed ; the intestine long 

 and slender ; the coeca very small, or wanting. 



The feet are of moderate length, sometimes rather long ; 

 the tibia bare to some extent ; the tarsus little compressed ; 

 the hind toe extremely small and elevated, with a large 

 conical decurvcd or deflexed claw ; the anterior toes slender, 

 webbed ; the claws arched, compressed, acute. 



The plumage is full, soft, rather dense or compact on the 

 back and wings ; the latter elongated, rather narrow, and 

 pointed ; the tail short. 



As we have but few species, belonging to three genera, it 

 is not necessary to present a general history of these remark- 

 able birds. The genera mostly adopted by systematic writers 

 are: — Diomedca, Procellaria, Fulmarus, Daption, Prion, 

 Puffinus, and Thalassidroma, all the species of which are 

 Avanderers on the face of the ocean, seeking their subsistence 

 among the varied substances floating there, or the fishes and 

 other animals that come within reach, none of them diving 

 in pursuit of prey, although they dip or plunge into the water 

 to secure it. They are remarkable for the quantity of oil 

 contained in their capacious gullets, and which, on being 

 wounded or seized, they vomit, some of them, it is said, also 

 squirting it through their tubular nostrils. Many of them 

 nestle in holes and crevices, laying one only, or a few white 

 eggs, in which respect they difter from the Larinse. 



STI^OFSIS OF THE BRITISH GENERA ANB SPECIES. 



GENUS I. FULMARUS. FULMAK. 



Bill rather short, strong, moderately compressed toward 

 the end, straightish, but with the tip of the upper mandible 

 much decurved, and acute ; the dorsal plate broad, the nostrils 

 opening directly forwards, and separated only by a thin sep- 

 tum ; lower mandible with the sides erect, and widely grooved 

 longitudinally. Legs of ordinary length ; tarsus rather stout. 



