based on the principle of Cephalization.—Herbivores, 161 
See on this point, Art. I, p. 828, and beyond, p. 179. 
Mutilates consequently differ from aquatic Herbivores funda- 
mentally in (a) being mult‘plicate structures, as manifested in 
their limbs and teeth, as well as in the less important fact of great 
length of body behind; and also ()) in being more elementalized 
structures, as shown in the reptile-like teeth. 1e type is 
eminently, therefore, a multiplicate and elementalized type, and 
thus stands apart from that of the Sirenians,’ 
2. Prosthenic, metasthenie and urosthenic distinctions among Her- 
bivores.—The distinctions, prosthenic, metasthenic and urosthenic 
appear to be an important basis of subdivisions under the Her- 
bivorous type. 
The urosihenic species (or those using the caudal extremity for 
locomotion) are the Sirenians, as the Dugong and Manatus, 
The distinction of prosthenic and metasthenic is manifested 
among the other Herbivores in two ways: (1) a higher or pre 
mary, in the general structure; and (2) un inferior or secondary, 
in the extremities of the limbs. 
(1.) Ln the general structure —Under this method, the prosthente 
species are those in which the fore-limbs are the stronger pair, 
and the melasthenic, those in which the hind-limbs are the 
stronger. The former include the Proboscideans, Rhinoceroses, 
apirs, Hogs and Hippopotamids. The Hog is particularly 
strong in the neck and fore-quarters. It is well known t 
fatted hog often loses the use of its hind-limbs from overgrowth, 
and not of the fore-limbs, although the fore-limbs carry not only 
their share of a body nearly equally divided between the limbs, 
but also the heavily weighted head. ’ 
The metasthente species are the Solipeds and the Ruminants, 
in which the hind-limbs are well known to be the strong Pe 
Th f-de- 
* Thi iti t only the Sirenians but also the Zeuglodonts, which 
have ‘ oon begtig paris with normal teeth and nostrils, although very 
elongat ie. 
4 sae “= baer eeded than mere ree te hind- 
lim consequen these metasthenic species are not good for this kin 
Oe teat a ot cat length of limb,-too little real strength for the 
long and steady pull which it requires, and which is very different from the mere 
