1916.] 



CYNOMYS GUNNISONI ZUNIENSIS. 



33 



Molt. — The molt of C. g. zuniensis is much more conspicuous than 

 in the northern subspecies. May specimens are frequently in a 

 very ragged state, with very little indication of renewal. Speci- 

 mens in complete summer coat, including the tail, are rarely taken 

 before July 1. The summer coat frequently is so rapidly worn and 

 bleached as to change the entire appearance of the animal before 

 there are any traces of the fall pelage. The new pelage of autumn 

 first appears in adults over the posterior half of the body about 

 September 1. No specimens in full winter coat have been seen 

 which were killed earlier than November 1. 



SlcuU. — As in C. g. gunnisoni but averaging larger and more 

 heavily built. 



Measurements. — Type specimen: Total length, 363; tail vertebrae, 

 53; hind foot, 60. Shull: Condylobasal length, 57.9; zygomatic 

 breadth, 43.8; mastoid breadth, 29.1; length of nasals, 22.4; length 

 of mandible, 43; maxillary tooth row, alveoli, 15.6. Averages of 9 

 specimens from Arizona: Total length, 355 (330-373); tail verte- 

 brae, 62 (54-68); hind foot, 60 (57.5-62.5). SJcull: Condylobasal 

 length, 55.8 (51.9-57.8); zygomatic breadth, 43.5 (39.7-45.5); mas- 

 toid breadth, 27.4 (25.7-28.6); length of nasals, 21.9 (20.6-23.5); 

 length of mandible, 42.7 (40.3-44.2); maxillary tooth row, alveoli, 

 14.5 (14.2-14.8). For detailed measurements of specimens see 

 page 35. 



Weight. — ^An adult male collected at Acoma, New Mexico, Sep- 

 tember 28, weighed 2 pounds. 



Type specimen. — No. 137555, U. S. National Museum, Biological 

 Survey collection. Adult male, skin and skull (teeth considerably 

 worn). Collected at Wingate, New Mexico, June 26, 1905, by N. 

 Hollister; original number 2374. Except on the tail the skin is in 

 fresh summer pelage. 



Remarks. — This well-marked-color subspecies of Oynomys gun- 

 nisoni occupies the arid southwestern part of the range of the species 

 and is the common prairie-dog of large parts of New Mexico and Ari- 

 zona. Material from southwestern Colorado is not plentiful, but the 

 specimens examined indicate that the range of the pale form extends 

 into that portion of the State. Specimens are wanting from the 

 near-by section of Utah, where this form undoubtedly occurs. 

 Specimens from Flagstaff, Arizona, and the vicinity of San Francisco 

 Mountain in general are slightly darker, more drab, than skins from 

 eastern Arizona and western and central New Mexico, but on the 

 whole the form is very uniform in coloration throughout its range. 

 While in the main an Upper Sonoran form, this prairie-dog is gener- 

 ally distributed in the Transition Zone parks of numerous mountain 

 20651°— 16 3 



