MAMMALIA. 631 



Aflev. 1852. (Besides other characters this species is distinguished by 

 17 ribs, whilst the Brasilian has oaly 15 or 16.) Manatus australis is 

 figured by HoMBOLDT, Wiegmann's Archiv f. Naturgesch. 1838, Taf. i. 

 ir; to this also belong Stannius Beitrage zur Kenntniss des Amerika- 

 nischen Manati. Mit 2 lith. Taf. Rostock, 1845, 4to. 



The third species Manatus senegalensis Desmar., occurs on the west 

 coast of Africa under the tropics; see Adanson ITist. nat. du Senegal, 

 p. 143 ; the skull is figured by Cuvier Rech. sur les Oss. foss. v. i, PI. 

 19, figs. 4, 5. 



These animals attain a length of from 12' to 15' or more; their flesh, 

 like that of the dugong, is eatable, and is famed as being palatable. 



b) Fo7a' distinct extremities. 



Oeder IV. Pachydermata. 



Feet ungulate or furnished with nails which are flat and ungu- 

 lar, monodactylous, tridactylous, tetradactylous or pentadactylous. 

 Molar teeth in both jaws, tuberculate, complex or lamellose, with 

 crown hroad, suitable for triturating ; incisors and canines some- 

 times none. Stomach simple. (Ungulate animals, not ruminating 

 vegetable food ; with skin mostly thick, often thinly haired.) 



The Pachyderms. Although a fossil genus [Anoplotherium) is 

 furnished with two hoofs only, and in the hog not more than two 

 hoofs rest on the ground, whilst two others, smaller and accessory, 

 are raised above the ground (ungulce succenturiatcB s. accessorice), as 

 in many ruminant animals, yet these last, the ruminants, ai'e not to 

 be confounded with the former order. Of these the carpal and 

 tarsal bones correspond in number to the number of the fingers, and 

 do not coalesce to form a single bone. They have not a compound 

 stomach, and never ruminate. All these animals are exclusively or 

 principally herbivorous. We admit, however, that this order 

 scarcely deserves the name of a natural division ; and there is, for 

 example, between Hyrax and Elephas in all the characters a differ- 

 ence almost as great as that between the bodily sizes of the two. 



The ungulates are distinguished by the odd or even mimber of 

 their toes ; an arrangement first proposed by Cuvier Rech. s. I. 

 Ossem. foss. sec. ed. 4to, iii. p. 72, but afterwards abandoned. It 

 was again advanced and strongly defended by Owen in works cited 

 below (p. 634). The elephants, from their peculiarities of structure, 

 foi-m an aberrant group. The remaining ungulates (with the 

 exception of the ruminants which we regard as a distinct order) 

 are grouped according to the odd or even number of their toes. 



