40& SMITHSONIAN MISCELLANEOUS COLLECTIONS [vOL. 45 



antero-superior angle is rather obliquely rounded off. The anterior 

 edge of the acetabulum is about midway between the extreme anterior 

 and the extreme posterior points of the bone. The obturator foramen 

 is less rotund than it is in Lcpns. 



The femur, the tibia, and the fibula of Oryctolagns are typical for 

 the family Leporidge, as detailed in the general account (p. 382), and 

 show nothing that is peculiar to the genus. 



The greatest length of the foot about equals the length of the tibia. 



The basal width of the metatarsus is contained two and a half times 

 in the length of the third metatarsal, as is commonly the case among 

 the Leporidse. 



The combined length of the phalanges of the two lateral digits, as 

 well as of the two middle ones, is approximately equal to the length 

 of the metatarsals to which they belong. 



Species in the genus. One, O. ciinicuhis (Linn.eus). 



Oryctolagns is a well-marked genus. In spite of a rather extensive 

 geographic distribution, only one species has been recognized. It 

 seems to have few relationships with the other Old World genera. 

 With Sylvilagus in America, it has certain points of resemblance, 

 in the shape of the transverse processes of the lumbar vertebrse, of 

 the scapula, in the relative size of the radius and ulna, in the shape 

 of the pelvis and of the ribs and sterna. The skulls of the two 

 genera taken as a whole are not markedly different, and the teeth are 

 essentially alike. 



Oryctolagns has been extensively domesticated, and many stable 

 varieties produced, among them the Belgian hare, but the true generic 

 characters are never lost, and some of them, as the keeled presternum 

 and the large anapophyses of the lumbar vertebrae are even better 

 marked in the domestic rabbits than they are in the wild ones. 



Genus LIMNOLAGUS Mearns 



1867. Hydrolagus Gray, Ann. I\Iag. Nat. Hist., xx, 3d sen, 1867, p. 221. 

 1897. Limnolagus Mearns, Science, n. s., v, March 5, 1897, p. 393. 

 1899. Limnolagus Major, Trans. Linn. Soc. London, 2d ser., vn, Zool, 

 November, 1899, p. 514. 



Type. — Limnolagus aqnaticns (Bachman). 



Geographical Distribution. — Austro-riparian faunal area of North 

 America, in general the South Atlantic and Gulf states. 



Diagnosis. — Externally similar to Sylvilagus, but pelage harsher; 

 ear, tail, and hind foot relatively shorter, the latter scantily haired. 

 Skull much as in Sylvilagus, but postorbital process fused to side of 

 cranium for its whole length, forming neither notch nor foramen. 



