MAMMALIA. 629 



477 491, du Dugon de BUFFON; see also OZERETZKOVSKY in Nov. 

 Act. Acad. Sclent. Petropol. ad annos 1795, 1796, Tom. xin.), and 

 the great CUVIER also improved the systematic arrangement as 

 regards these animals, inasmuch as the resemblance which this 

 family bears to the walrus is merely superficial and external. On 

 the other hand, it cannot be overlooked that there are many 

 important peculiarities in the whole organisation which distinguish 

 the herbivorous from the true cetaceans, and that therefore the 

 union of these two families in one order is exposed to objections 1 . 

 There are however difficulties of no less weight which oppose the 

 union of the lamantins with the pachyderms. 



The intestinal canal is long in these animals, and surpasses the 

 length of the body eleven, fourteen, in the animal of STELLER 

 twenty times. The stomach has two blind appendages at the 

 pyloric portion, at least in the lamantin and the dugong; the 

 pyloric portion is separated from the cardiac by a constriction ; the 

 cardiac portion is a blind appendage beset with many follicles. 

 The heart is divided at the apex by a deep fissure (see various 

 figs, in HOME Lectures, Yol. iv.). The ribs are numerous (15 19 

 pairs) j in all, the Manatus included, there are traces of bones of 

 the pelvis. These animals feed on marine plants (Ftcci), and keep 

 near the shores of the sea and the mouths of rivers. 



Rhytina ILLIG., Stellera Cuv. 2 Teeth none; a lamella with 

 undulating surface, scarcely containing any calcareous matter, com- 

 posed of horny tubules, covering both jaws internally. Head small. 

 Body covered with thick, fibrous, fissured epidermis. Caudal fin 

 lunate. 



Sp. Bhytina Stelleri DESM.,WAGN , Trichechus M anatm borealis GM., PALLAS 

 Zoogr. Rosso-Asiat. I. p. 272, Icon. Fas. 2. This animal, which attains a 

 length of twenty-four feet, formerly lived in the neighbourhood of the coast 

 of Kamschatka at Behring's Island, and was discovered and described by 

 STELLER in BEHRING'S second voyage ; see Nov. Comm. Acad. Sc. Petrop. 

 Tom. ii. ad annum 1749, pp. 294 330 (and in a separate publication in 

 German, Ausfiihrliche Beschreibung von sonderbaren Meerthieren, Halle, 

 1753, 8vo). Since 1768 this animal has not been seen; on the discovery 

 of BEHRING'S Island, which was uninhabited, its distribution had already 

 become exceedingly limited. See VON BAER'S masterly Untersuchungen 

 iiber die ehemalige Verbreitung u. die gandiche Vertilgung der von STELLER 

 beobachteten Nordischen Seekuh, St. Petersburg, 1838, 4to (Mem. de FAcad. 

 imp. des Sc. de St Petersb. vi. Se'rie, Tome v.). Of the dental laminse 

 BRANDT has given extensive details with figures, Mem. de I' Acad. imp. des 



1 Compare OWEN, Proceedings of the Zool. Soc. 1838, pp. 28 45. 

 3 Or Stellerus? DESMAR. Encycl. method. 



