.1 New Rabbit from México. 173 



family circle of the Leporidse muat be extended to include the 

 new meniber.* 



From the foregoing it will be evident that the new animal ia 

 of unusual interest to naturalista. The curious combination of 

 its anatómica! characfcers, the peculiarity of its nimle of looonio- 

 tion, the oddity of its babits, and the isolatioa of its home 

 higb up on lofty Popocatepetl — give it an interest quite apart 

 from that whieh atfcaches to most new discoveriea. For tliis 

 reason itaffords me special pleasure to bestow upon the new and 

 remarkable genua, of which it is the type, the ñame Romerolagus, 

 in honor of the venerable Señor Don Matías Romero, Envoy 

 Extraordinary and Minister Plenipotentiary from México, as a 

 slight token of appreciation for the active interest he has taken 

 in the explorations of the United States Biological Survey in 

 México, and in recognition of the many courtesiea he has ex- 

 tended to our field naturalists during the past five years. 



ROMEROLAGUS gen. nov. 



Tupe. — Romerolagus nelsoni sp. nov., from Mt. Popocatepetl, México. 



Diagnosis. — Size small; eara exceedingly short, shorter than in any 

 known speciea of Lepiis; hind leus and feet short; skull much as in Lepus 

 (subgenus Sylvilagus), except that the postorbital processes are small, di- 

 vergent, and wauting anteriorly, and the jugáis much elongated poste- 

 riorly ; clavicle complete and articulating with hoth sternum and scapula ; 

 presternutn broadly expanded anteriorly, much broader than long in front 

 of first pair of ribs [narrowand slender ¡n Lfpnx]; mesosternum of 3 seg- 

 ments [4 in Lepwi] ; 6 paira of ribs articulating with sternum [7 paira in 

 Lepus"] ; transverse procesa of 5th cervical vertebra directed straight out- 

 ward (i astead of backward), its inferior lamella lacking the usual posterior 

 extensión ; transverse processes of all lumbar vertebne broadly expanded, 

 their bases covering entire length of vertebne ; hypopophyses preaent on 

 first :; lumbar vertebne, but small ; interior crest of navicular bone short 

 and not produced under base of metatarsal. 



Romerolagus nelsoni sp. nov. Popocatepetl Rabbit. 



Type from Mt. Popocatepetl, México (altitude 3,350 meters or 11,000 

 feet!. No. 57949, r?ad., U. S. Nat. Mus., Dept. Agrie, coll. Collected Jan. 

 l!, 1894, by E. W. Nelson and Ii. A. Goldman. Original number 563;). 



Geographic distribution. — Boreal Zone of Mt. Popocatepetl, between the 

 altitudes of 3,050 and 3,660 meters (10,000-12,000 feet). 



*It is singular that of the four characters given by Flower and Lydek- 

 ker in the first sentence of their diagnosis of the family Leporidse ("im- 

 perfect clavicles, elongated hind limbs, short recurved tail, and long 

 ears"), not one applies to the Popocatepetl rabbit. 







