242 Ho well Three New Skunks. 



Remarks. This species differs strikingly in external characters from 

 Spilogale interrupta of the plains, while from leucoparia and gracilis it 

 may be readily distinguished by its skull characters. It is apparently 

 a mountain animal, but is at present known from only two localities 

 Arkins and Estes Park, Colorado. 



Spilogale angustifrons sp. nov. 



Type from Tlalpam, Valley of Mexico, $ adult, No. 50,825, U. S. Nat. 

 Mus., Biological Survey Collection. Collected Dec. 15, 1892, by E. W. 

 Nelson and E. A. Goldman. Original number, 4035. 



General characters. Size small; coloration as in S. ambigua, but usu 

 ally without the white bands on thighs. Skull slender, and without 

 prominent ridges. 



Skull. Similar to that of ambigua, but smaller and narrower; cranium 

 highly arched; rostrum narrow: audital bullae relatively large and high; 

 molars smaller than in ambigua, the carnassial teeth decidedly so. 



Measurements. Average of 3 adult males from type locality: total 

 length, 345; tail vertebrae, 130; hind foot, 40. Skull (of type): basilar 

 length, of Hensel, 43; zygomatic breadth, 31.3; mastoid breadth, 27.5: 

 interorbital breadth, 13. 



Remarks. This form belongs with the group of narrow-skulled species 

 inhabiting the eastern United States, in which group ambigua also be 

 longs. Intergradation with the latter species is probable, thc-ugh no in 

 termediate specimens have been examined. The present form occupies 

 the southern portion of the Mexican table-land, from Guanajuato to 

 Chiapas. 



Spilogale angustifrons tropicalis subsp. nov. 



Type from San Mateo del Mar, Oaxaca, $ adult, No. 73,523, U. S. Nat. 

 Mus., Biological Survey Collection. Collected May 16, 1895, by E. W. 

 Nelson and E. A. Goldman. Original number, 7958. 



General characters. Similar to angustifrons, but larger; skull with 

 smaller teeth and larger mastoid capsules. 



Skull. Larger and more angular than that of angustifrons; mastoid 

 capsules more inflated; audital bullae flatter; rostrum broader: upper 

 molars and last lower molars relatively smaller. 



Measurements. Average of 3 adult males from type locality: total 

 length, 378; tail vertebrae, 144; hind foot, 44.7. Skull (of type): basilar 

 length of Hensel, 47; zygomatic breadth, 33; mastoid breadth, 30.5; inter- 

 orbital breadth, 14.5. 



Remarks. This form occupies the tropical lowlands of Oaxaca, inter- 

 grading apparently with angustifrons in the neighborhood of Tehuan- 

 tepec. Its skull resembles that of ambigua quite closely, but has 

 decidedly smaller teeth and larger mastoid capsules. 



