40 FIELD MUSEUM or NATURAL HISTORY ZOOLOGY, VOL. X. 



interorbital breadth 5.6; breadth of braincase 12.8; postpalatal length 

 12.2; three anterior molariform teeth 6.2. 



Remarks. The area of hairs with dark bases seems to be quite as 

 extensive in this form as in M. mitis. Therefore it seems scarcely pos- 

 sible that it is the same as M. m. casta in which this area is said to be 

 greatly reduced. 



The single specimen was brought to us by a boy who killed it with 

 a stick as it ran from an overturned corn shock. Considerable trapping 

 was done in the same field but none of this species was caught. 



Myrmecophaga tridactyla artatus subsp. nov. Venezuelan Ant-bear. 



Type (skull only) from Empalado Savannas, 30 miles east of Mara- 

 caibo, Venezuela. Adult. Collected March 19 ji by W. H. Osgood. 



Characters. Differs from M. tridactyla and M. t. centralis in its 

 much narrower nasals and less expanded maxillaries, making the 

 entire rostral part of the skull decidedly narrower; anterior lateral 

 extensions of frontals less produced than in centralis but more so than 

 in tridactyla; greatest depth of maxillary much less than in tridactyla; 

 antero-inferior production of parietal considerably exposed on ventral 

 surface of skull as in centralis. 



Measurements of skull. Greatest length 346 (344) ;* length of nasals 

 (median) 148.7 (150), (diagonal) 177 (178); greatest width of nasals 

 16 (19.6) ; least width of nasals 10 (14.2) ; greatest width of rostrum 22.3 

 (28.2); least width of rostrum 19.8 (24.3); greatest depth of maxillary 

 20.3 (20); least interorbital width 42.2 (45); median length of frontals 

 144.2 (140); mastoid width 54.4 (55.7); lacrymal 38.5 x 17.5 (31 x 18). 



Remarks. This form seems well distinguished from both M. tridac- 

 tyla of Brazil and M. t. centralis of Central America, the characters of 

 which have been so clearly pointed out by Lyon (Prfoc. U. S. Nat. Mus., 

 XXXI, pp. 569-571, pi. XIV, 1906). It is somewhat nearer centralis, 

 agreeing with that form in the character of the antero-inferior part of 

 the parietal and in the relatively shallow maxillae. In the relations of 

 the anterior productions of the frontals it is somewhat intermediate. 

 A specimen from Dibulla, Colombia, loaned by the Museum of Comp- 

 parative Zoology, evidently is referable to the new form although less 

 pronounced in its characters than the type; while one from Ciudad 

 Bolivar, Venezuela, belonging to the American Museum of Natural 

 History, is quite as definitely referable to the Brazilian form. 



Material is not as yet available to determine what external charac- 



* Measurements in parentheses are those of an adult skull of centralis (No. 15966) from Guatemala. 



