lvon] the hares and their allies 395 



Subgenus PCECILOLAGUS, new 



Type. — Lcpiis aincricaiius Erxlebex. 



Geographical Distribution. — The Canadian, Hudsonian, and 

 Transition zones of North America. 



Diagnosis. — External, cranial, and dental characters essentially as 

 in subgenus Lepus, but size smaller, greatest length of skull about 

 75 mm., portorbital process slenderer than in Lepus, its posterior 

 limb free behind, rostrum more pointed, groove on incisors simple, 

 shallow, and without cement. Spinous processes of lumbar vertebrae 

 low and triangular in form. 



Skull (pis. Lxxv, i; LXXN'i, I, 4; Lxxxiv; lxxxv, 6-12). — The 

 members of this subgenus are hares of medium size, the skull being 

 about 75 mm. long. The skull is less strongly arched than it is in 

 the true Lepus, but not so flat and long as in Maerotolagus. The 

 nasals and rostrum are narrower than they are in Lepus. The post- 

 orbital processes are much slenderer, less triangular than they are in 

 Lepus or Maerotolagus, free both in front and behind. They bear 

 considerable resemblance to the postorbital seen in Oryetolagus. 



Teeth (figure 44, 18). — The first upper incisors bear each a simple 

 shallow groove not filled with cement. The remaining teeth are as 

 in true Lepus. 



Vertebral Column. — The spines of the anterior dorsal vertebrae are 

 relatively shorter than they are in true Lepus, being equal to about 

 two and a half times the length of the centra, instead of three times. 

 The spinous processes of the lumbar vertebrae (pi. xciii, 2) are 

 also relatively lower in Pcccilolagus than in Lepus; they are tri- 

 angular in outline, with the posterior edge nearly straight, while in 

 the other subgenera the posterior edge is much cut out. 



Species included in this subgenus, see pp. 334 and 335. 



Subgenus MACROTOLAGUS Mearns 



1896. Maerotolagus ]\Iearns, Proc. U. S. Nat. Mus., xvni, p. 552, June 



24, 1896. 

 1899. Maerotolagus Major, Trans. Linn. Soc. London, 2d sen, vn, ZooL, 



pp. 468, 469, November, 1899. 



Type. — Lepus alleni Mearxs. 



Geographieal Distribution. — Mexico and the southwestern United 

 States. 



Diagnosis. — Size large, as in subgenus Lepus, ears longer than 

 head or hind foot, skull narrow, posterior limb of postorbital touch- 

 ing side of cranium, enclosing an oval foramen. 



