lyon] the hares and their allies 393 



articulate with the sternum. The sternal costal cartilages are very 

 short and wide as compared with the same structures in the other 

 genera. 



Shoulder Girdle and Upper Extremity. — The scapula (pi. xcvii, 

 I, 2) in Lepiis, especially in the larger members, has a tendency to 

 be relatively broad, with the superior border rather more convex 

 than it is in the other genera, with the antero-superior angle more 

 rounded, and with the supra-spinous fossa relatively wide. 



The radius and ulna (pi. xcviii, 1-3) show characteristics peculiar 

 to the genus. The ulna is much reduced in size along the middle of 

 the shaft, and except at the lower extremity it is placed almost entirely 

 behind the radius. The radius itself is rather long and slender. 

 The humerus and radius are usually subequal in length. 



The carpus, the metacarpus, and the phalanges of Lepiis are 

 entirely similar in form and position to these same bones in any of 

 the Leporidas as detailed in the general account of the wrist and 

 the hand. 



Pelvis and Loiver Extremity. — The ilium is broad and shovel-like 

 in the genus Lepns; its antero-superior angle is rounded off, but not 

 obliquely so, as in the case of the other genera. The distance from 

 the anterior edge of the acetabulum to the extreme anterior point of 

 the ilium is less than the distance from the former point to the most 

 distant point of the ischium. In all the other genera the former 

 distance is usually equal to or a little greater than the latter. The 

 obturator foramen is usually more rotund in Lepus than in the rest 

 of the family. 



The femur and the tibia and fibula (pi. xcix, i) of Lepns are 

 typical for the family, as detailed in the general account and show 

 nothing that is peculiar to the genus. 



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

 more often three times into the length of the third metatarsal, as is 

 commonly the case among the Leporidse (pi. c, 6). 



The combined length of the phalanges of the two lateral digits is 

 less than the length of the metatarsal to which they belong. The 

 combined length of the phalanges of the middle two digits approxi- 

 mately ec[uals the lengths of the metatarsals to which they belong. 



The genus Lepns possesses a number of skeletal characters quite 

 peculiar to itself and serving to separate it at once from all the other 

 genera of the Leporidse. Among these are form of postorbital proc- 

 esses, shortness of palate, reduced size of ulna, shape of anterior 

 ribs, shape of transverse processes of lumbar vertebrjE, and the 

 elongated form of the cervical vertebrae. Not one of these charac- 



