422 MERSATORES. PLUNGERS. 



Peculiarly erratic, they settle for a time only to rear tlieir 

 young, after Avhich they disperse ; yet some are to be seen at 

 every season, in almost every climate, on the barren shores of 

 Iceland, the picturesque coasts of Greece, the luxuriantly- 

 Avooded bays of the Indian islands, amidst the floating ice of 

 Nootka Sound, and on the sunny bosom of the Pacific Ocean. 



They may be generally characterized as having the body 

 ovate, rather light in proportion to their bulk ; the neck of 

 moderate length, or short; the head lai-ge, broadly ovate, 

 anteriorly narrowed. The bill of moderate length, generally 

 stout, but often slender, straight, compressed, more or less 

 decurved at the end, and opening to beneath the eyes. The 

 mouth is rather wide, and extensile ; the tongue fleshy, 

 tapering, pointed, horny beneath at the end. The oesophagus 

 very wide, its walls thin ; the proventricular portion dilated ; 

 the stomach small, muscular, with large radiated tendons, and 

 thick, dense, rugose or plicate epithelium ; the intestine rather 

 long, narrow, or of moderate width ; coeca very small, cylin- 

 drical ; rectum with a large globose cloaca. 



The nostrils are rather large, sub-basal, or medial ; the 

 eyes rather small, with feathered eyelids, having crenulate 

 margins. The apertures of the ears of moderate size. The 

 legs never of great length, generally short, rather slender ; 

 tibia bare to some extent; tarsus little compressed; toes of 

 moderate length, slender, spreading, webbed, the first very 

 small and elevated, or wanting ; claws small, arcuate, rather 

 obtuse. The plumage full, close, and soft ; the feathers 

 generally oblong and rounded ; the wings very long, rather 

 narrow, much pointed ; the tail generally moderate, and 

 mostly of tAvelve feathers. 



Tlie Mersatorial Order, of Avhich any member may be at 

 once recognized, is more homogeneous than the others. It 

 may, however, be divided into a few somcAvhat distinct fami- 

 lies. The Procellariinje, of wliich the greater number of 

 species belong to the southern hemisphere, and of Avhich 

 many are of gigantic or large size, have few representatives 

 with us, and they, with exception of one, among the smallest 

 of all sea-birds. The genera arc Dioniedea, which includes 

 the most celebrated of the sea-birds, the Albatross, Procel- 



