SPECIES OF MAMMALIA. 



Family IL—Cete (Common Cetacea.) 



Teeth sometimes pointed, sometimes obtuse ; all of one 

 sort on the edges of the jaws; sometimes no teeth, but 

 transverse corneous laminss in the vault of the palate; 

 two anal mammae ; nostrils opening on the top of the 

 head to eject water, called spiracles; olfactory nerve small ; 

 larynx pyramidal, penetrating the back; nostrils flatted ; 

 eyes with thick sclerotica ; smooth tongue ; no hairs, 

 eyelash, or mustachios; skin smooth and shining, covering 

 a thick coat of fat ; stomach with five and sometimes 

 seven pouches ; spleen divided into many separate lobes. 



Tribe I — Small-headed Cetacea. 

 Head in the usual proportion with body. 



Genus I. — Delphinus, Linn. (Dolphin.) 



Teeth of one sort, canine form, compressed and indented 

 on their trenchant edge ; number very variable, two hundred 

 at most, two at least, or none ; jaws more or less advanced, 

 beak-formed; no tusks; spiracles with a common and 

 crescented aperture above ; sometimes an adipore dorsal 

 fin ; sometimes a longitudinal dorsal fold of skin ; tail 

 flatted horizontally, and bifurcated : no caecum ; carnassial. 



Sub-genus I. — Delphinus (Dolphins proper) Cuvier. 

 Muzzle elongated into a moderate beak; large at base, 

 rounded at point ; Jaws widened posteriorly, with edges 

 furnished with numerous teeth: a single dorsal fin. 



903. 1. D.Delphis (Common Dolphin.) Jaws moderately 

 elongated, of equal length, forty-two to forty-five ttrtli 

 each side, fine, round, pointed, arched, ociuidistant, from 

 forty-two to forty-five in each jaw; dorsal fin placed bc- 



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