SPECIES OP MAMMALIA. 



on the highest part of the head behind ; longitudinal dorsal 

 projection, not ; fin pectorals, oval ; manners like the Dol- 

 phin's ; carnassial. Inhabits the Northern Seas. 



918. 1. Monodon MonocerosiCommon'Nsirwha.l.) General 

 form ovoid ; length of head one-fourth that of the animal ; 

 left tusk unique (the right not being developed), of spiral 

 form, one half as long as the body ; back uniformly grayish 

 in the young, blackish or marbled in the old ; twenty or 

 tvi^enty-two feet long. 



Monodon, Artedi. Narwhal, Oder Einhorn Anderson, 

 Muller. Monodon Narwhal, i^a&n. Monodon Monoceros, 

 Lin.y Erx.y Gm. Narwhal, Bonnat. Narwhal Vulgaire, 

 Lacep., Shaw, Vulgo. Sea-Unicorn. 



Icon. Encyc. Get. Lacep. Shaw. 



Habitat. Eightieth degree of North latitude. 



Obs. M. Microcephalus and M. Andersonianus, not au- 

 thenticated. The last is represented as having smooth 

 tusks. 



Tribe II. — Large-headed Cetacea. 



Genus I. — Physeter, Linn. 



Lower teeth eighteen to twenty-five each side of the 

 jaw ; upper jaw wide, elevated, without corneous laminaj 

 or teeth, or with short and undeveloped ones; lower jaw 

 elongated, narrow^, corresponding to a furrow of the upper ; 

 thick and conic teeth entering corresponding cavities in 

 the upper; orifice of spiracles united at the end or near the 

 upper end of the muzzle; dorsal fin in some species, 

 simple eminence in others. Large cavities with cartilaginous 

 walls in the upper region of the head, communicating with 

 diverse parts of the body by particular canals, filled with 

 an oil which fixes and crystallizes when cool; carnassial. 

 Inhabit the Polar Seas. 



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