30G 



MAMMALIA. 



are arranged in transverse rows on the back and tail, so as to form a movable 

 dermal armour (fig. 687). The limbs are short, and with their powerful 

 scraping claws are well adapted for burrowing. Incisor teeth are absent, except 

 in Dust/pus gi-a-cinctiis and in the fossil Clila/m-ydotherium. Both jaws have 

 small cylindrical grinding teeth, the number of which varies in the different 

 forms. They inhabit South America. iJiixi/jiit.* itocrmcinctiix L., the long- 

 tailed Armadillo, with eight to ten bands : D.j/ if/as, with upwards of a hundred 

 teeth ; Clilamydophomx trnncntits. Hart, the Pichyciego, in the neighbourhood 

 of Mendoza. 



Fam. Bradypoda ( Sloths). With rounded head (fig. 686) and anteriorly directed 

 eyes, with very long anterior limbs and pectoral mamma;. The incisor teeth, 

 and sometimes also the canines, are absent ; there are three to* four grinders in 

 each half of the jaw. The large process on the jugal. descending over the lower 

 ja\v, is worthy of remark. The Sloths are exclusively arboreal ; they use the 

 curved claws at the end of the two or three closely connected digits for hanging 

 on to branches during their strong but slow movements. On the ground they 

 can only drag themselves along extremely awkwardly and helplessly. The 



FIG. R87. Dasypus gigas. 



body is covered with long and coarse hair, like dry hay. They live in the 

 forests of South America. Bradypue tridactyluR Ouv., AY. or three-toed Sloth : 

 lir. toi-quatii.t 111.. ClioltfjiHx d \ (1 a et i/l H x 111.. Unau. or two-toed Sloth. 



Order 4. CETACEA.* 



Aquatic Mammalia with spindle-shaped body which is nut covered 

 n-ifh hair ; with Jin-like front limbs ai! horizontal caudal fin. Tie 

 posterior limbs are absent. 



The Whales repeat the piscine type in the form of their body and 

 in the articulation of their skeleton (Fig. 688). By their whole 

 organisation they are true Mammals with warm blood and pulmonary 

 respiration, and they are most nearly allied to the Ungulates, which 

 they approach through the Rirenia. Some species attain a colossal 



* D. F. Eschricht. " Zoologisch-ajiatomisch-physiologische Untersuchungen 



die nordischen Walthiere," Leipzig, 1849. 

 D. F. KsHirirht og J.Reinhardt, -'Om Nordhvalen.'' Kjobenhavn. ISC. I. 



