MAMMALIA. 



IlyJromyt Coyput. Coypou, pi. 54. f. 9. Incisors }, 

 no canines; grinders ? I, flattened on the crowns, with 

 enamelled ridges in the form of the figure 8 ; all the feet 

 provided with five toes; thumb of fore feet very small; 

 hind t'oet palmated ; toes united by a membrane ; tail 

 cylindrical, length of the body, and acutely tapering. 



1st Sub-division. Spineless rats of the old Continent. 



Jfut Sylraticus. Field Mouse, pi. 54. f. 40. Incisors }; 

 no canines ; molars f i, tubercular ; ears oblong or round- 

 nl, almost destitute of hairs; fore feet four toed, and a 

 wart for a thumb, covered with an obtuse nail ; hind feet 

 five toed ; tail long, without huir, and somewhat scaly. 



2nd Sub-ditision. Destitute of spinet. American Rats. 



Mus rufus. Red Rat. Fur yellowish red ; darker 

 on the head and back ; abdomen yellowish, 6 inches long. 

 Inhabits Paraguay. 



3d Sub-division, Spinous Rats. 



Mtu Perchal. Perchal Rat, pi. 64. f. 10. Fur redd- 

 ish brown above, with spiny hairs intermixed ; gray 

 underneath ; body 18 inches long ; inhabits Pondi- 

 cherry, in India. 



Cricetut rulgaris. Common Hamster, pi. 53. f. 44. 

 Incisors J; no canines; molars J i; provided with cheek 

 pouches; head thick; ears rounded and oval; fore feet 

 with four toes, and the thumb represented by a nail ; hind 

 feet with five toes. 



Geomys Douglasii. Douglas's Geomys, pi. 52. f. 44. 

 Incisors f; no canines; molars i }; head large, depressed; 

 nose short; nostrils are small, round openings, facing 

 downwards somewhat laterally; mouth small ; with large 

 and pendulous cheek pouches; eyes small, far apart; body 

 cylindrical; legs short with five toes in each foot. 



Diplostoma Douglasii. Douglas's Camas Rat, pi. 54*. 

 . 29. Incisors J, furrowed; no canines; molars 1 J; 

 cheek pouches very large, with exterior openings. 



Dipus gerboa. Jerboa, pi. 54. f. 22. Incisors f, lower 

 ones acute ; no canines ; molars i % or i i; eyes large ; 

 ears long, pointed ; fore feet four toed, and nailed tubercles 

 representing a thumb; hind legs five or six times the 

 length of the fore ones, with from three to five toes. 



Gerbillut Canadensis. Labradore Sweeping Mouse, 

 pi. 54. f. 5. Incisors f; no canines; molars < J; ears 

 moderately short ; fore legs short ; four toed ; hind legs 

 being long; feet with five toes, each provided with a nail-, 

 tail long, hairy. 



Aspalax Typhlus. The Spalax, pi. 54. f. 4. Incisors f; 

 no canines; molars I J; with tubercular crowns; eyes ex- 

 tremely small; no external ears; feet short; with five 

 toes ; tail naked ; fur soft and short. 



Balhyergus maritimus. Coast Bathyergus, pi. 54. f. 1. 

 Incisors J, very large and long ; no canine teeth ; molars 

 1 1 or i i; body thick, cylindrical ; head thick ; muzzle 

 truncated; eyes small; no external ear; feet and tail 

 short 



Pedetes Capensis. Cape pedetes, pi. 54. f. 3. Incisors 

 f; no canines; molars J -J: lower incisors cut obliquely; 

 molars consisting of two elliptical parts; head short, large, 

 and depressed ; muzzle obtuse ; ears long, narrow ; eyes 

 large; all the feet four-toed. Females provided with an 

 abdominal pouch. 



Arctomys marmotta. Alpine Marmot, pi. 54. f. 7. 

 Incisors f, very strong; no canines; molars J |, upper 

 surface ridged and tubercular; body thick; head and 

 eyes large ; ears short ; no cheek pouches ; fore feet four- 

 toed; hind feet five-toed; tail very short. Habits 

 social. 



SpermopJiilus Franklinii. Franklin's marmot, pi. 53. 

 f. 45. Incisors f, strong; no canines, molars J 5; head 

 somewhat large, with large cheek pouches; tail long in 

 most of the species ; habits solitary. 



Capromys Furnieri. Fournier's Capromys, pi. 54. f. 

 8. Incisors J, very strong, transversely truncated ; no 

 canines; molars J {; body bulky; fore legs short, with 

 four toes and a rudimentary thumb; hind feet with five 

 toes ; tail long, thick at the base, scaly. 



Sciurut Hudsonius. Chickasee squirrel, pi. 53. f. 46. 

 Incisors }, flat in front; no canines ; molars { J, tubercu- 

 lar ; head small ; eyes large ; ears erect ; fore feet four- 



toed; hind feet five-toed; nails long and curved; tall 

 long, with long bushy hair. 



Pteromys rolucella. Lesser American Fljing Squirrel, 

 pi. 5. f. in. Incisors }; no canines; molars < '; head 

 and ears round ; eyes large ; skin on the sides of the body 

 diluted, and extending from the fore to the hind legs, 

 forming a kind of parachute; tail long and villose. 



Section II. With imperfect clavicles, or none. 



Hystrix cristata. Crested Porcupine, pi. 53. f. 50. 

 Incisors f; canines none; molars i i; head thick; ears 

 short; tongue with spiny scales; body covered with long 

 and strong moveable spines, intermixed with hair; tai. 

 short; fore feet with four toes; hind feet with five. 



Atherurafasciculata. Fasciculated Porcupine, pi. 55. 

 f. 13. Incisors f ; no canines ; molars i i; head strong, 

 forehead depressed ; ears short, roundud ; fore feet with 

 four toes, and a rudimentary thumb ; hind feet with five 

 toes ; tail one-third the length of the body, scaly, tip pro- 

 vided with a tuft of bristles ; body covered with spines, 

 from the head to the root of the tail. 



Chinchilla lanigera. Chinchilla, pi. 54. f. 11. In- 

 cisors |; no canines; molars J i; head round; eyes large- 

 ears very large ; fore feet four-toed, and a rudimentary 

 thumb ; hind feet four-toed, external toe short, and placed 

 far behind ; tai! half the length of the body. 



Lepus cuniculus. Rabbit, pi. 54. f. 15. Incisors *, 

 upper in pairs; no canines; molars J J; eyes and ears 

 large; anterior feet with five toes; posterior with four, all 

 covered with hair beneath; tail short, erect. 



Lagomys Alpinus. Pika, pi. 54. f. 14. Incisors J; no 

 canines; molars f f; ears moderate; no tail; clavicles 

 nearly perfect ; feet same as the rabbit. 



Hydrochairus capybara. Capybara, pi. 53. f. 47- 

 Incisors }; no canines; molars t \; muzzle compressed; 

 eyes large ; ears moderate, and rounded ; fore feet four- 

 toed and palmated ; hind feet three-toed ; no tail. 



Cavia Cobaya. Guinea Pig, pi. 54. f. 16. Incisors f ; 

 no canines ; molars i -J; body thick ; muzzle short, com- 

 pressed ; eyes large ; ears rounded ; legs very short ; fore 

 feet four-toed ; hind feet with three ; no tail. 



Dasyprocta Acuti. Agouti, pi. 54. f. 17. Incisors J ; 

 no canines ; molars -} i; head elongated ; forehead flat ; 

 muzzle flat; eyes large ; fore feet four- toed, and an obso- 

 lete thumb ; hind feet three-toed ; nails long and strong. 



Ccelogenus su'bniger. Brown Paca, pi. 54. f. 60. 

 Incisors f ; no canines; molars i 1; head obtuse, cheek 

 pouches ; five toes on all the feet, all the interior toes 

 small. 



ORDER VII. EDENTATA. 



Destitute of incisors in either jaw ; sometimes having 

 molars only ; some species are without teeth ; toes varia- 

 ble in number, protected by strong nails. 



Tribe I. Tardigrada. 



Face short, with canines and molars, or with the latter 

 only ; nails long, bent. 



Brady pous tridactylus. Three-toed Sloth, pi. 55. f. S. 

 No incisors ; canines 1 i; molars 1 S; canines larger than 

 the grinders; head small; muzzle truncated; lore legs 

 longer than the hind, having three toes, armed with falcate 

 nails ; fur thick, harsh, and long. 



Megathurium Ouvieri. Cuvier's Megathurium. No 

 incisors or canines; molars ff; with transverse furrows 

 on their crowns; body twelve feet long. Found in a 

 fossil state only, in Paraguay, South America. 



Tribe II. E/odientia, or digging Edentata. 



Muzzle generally elongated ; with molar teeth only, 

 sometimes none. 



Dasypus novcmcinctus. Nine- Banded Armadillo, pi. 

 55. f. 7. No incisors, or sometimes !; no canines; 

 teeth subject to great variety, varying in number from 

 28 to 68 ; head long, pointed ; mouth small ; tongue 

 tensible ; body wholly covered by scales ; fore feet four or 

 five-toed; hind feet with five toes; nails long, fitted b 

 digging; tail long. 



