182 MURIB-S. CASTOK. 



Lumbar vertebrae 7 



Sacral 4 



Caudal 20 



*a. Skull. Bolivia. — Tbe specimen figured uf) 



Waterhouse, Nat. Hist. Mamm. | Fmm m , Bri( w 



* 6 '^J- Eohvia. > Collection. 



*c. Skull. Chili. 



d. Skeleton. J 



e. Skull. From Mr. Stevens's sale-rooms. 



The Magellanic Ctenomts. Ctenomys mageLlanicus. 

 Waterhouse, Nat. Hist. Mamm. ii. p. 283. pi. 8. fig. 5 (skull). 

 a. Skull. Purchased of Mr. Bridges. 



The Bolivian Ctenomts. Ctenomys boliviensis. 



Waterhouse, Nat. Hist. Mamm. ii. p. 278. 



*«. Skull. Santa Cruz. Purchased of Mr. Bridges. — The specimen 



described by Mr. Waterhouse. 

 *b. Skull (smaller). 



The White-toothed Ctenomys. Ctenomys leucodon. 



WaterJwuse, Nat. Hist. Mamm. ii. p. 281. 



a, b. Skulls. Bolivia. Purchased of Mr. Bridges. — The specimens 



described by Mr. Waterhouse. 

 c. Skeleton. Bolivia. From Mr. Bridges' Collection. 



CASTOR. 



Teeth :— Incisors t| ; Molars ^;=20. 



1-] 4-4 ' 



The Beaver. Castor canadensis. 



Baird, Mamm. N. America, p. 355. pi. 47. fig. 1 (skull), 1859.— Owen, 

 Catal. Osteol. Ser. Roy. Coll. Surg. 1855, ii. B. d. 45. p. 163. 



Castor fiber canadensis, Blainr., Ost. G. Castor, pi. 2 (skull). 



Castor americanus, Brandt, Mem. Acad. St. Petersb. vii. p. G4. taf. 1. 

 fig. 2, taf. 2. figs. 6, 7 (skull), taf. 3, 4 (skull). 



Cervical vertebrae 7 



Dorsal 14 



Lumbar 5 



Sacral 4 



Caudal 25 



a. Lower jaw, right side. 



b. Skull (from a black variety). Hudson's Bay. Presented by the 



Hudson's Bay Company. 



