1904.] Allen, Mammals from Santa Marta, Colombia. .\ 2 5 



Taking the skulls as a basis for comparison, T. torvum and 

 T. tajacu do not differ appreciably in size, as shown by the 

 subjoined tables of measurements, but they are readily sepa- 

 rable on other cranial characters, notably by the difference in 

 the facial angle, through the greater depth of the occipital 

 portion of the skull. With the total length and zygomatic 

 breadth absolutely the same (in the average) in both, the 

 depth of the occiput (top of the occipital crest on the median 

 line to lower border of occiput) in T. tajacu is 80 mm. and 

 in T. torvum 74.5 mm. This gives, approximately, a facial 

 angle of 55 for tajacu and a facial angle of 64 for torvum. 

 In addition to this, the audit al bullae are slightly larger 

 and the dentition is appreciably weaker in tajacu than in 

 torvum, as' shown in the subjoined tables. On the other hand, 

 T. torvum is much like the northern forms of the genus (angu- 

 latum and allies), but the skull is very much smaller, and, as 

 already shown, the coloration is distinctly different. 



The type locality of T. tajacu being Paraguay, the Chapada 

 (Matto Grosso, Brazil) series of skulls here used as representing 

 that species is presumably typical, Chapada being close to 

 the northern border of Paraguay. They were collected by 

 Mr. Herbert H. Smith in 1885. All the skulls in both tables 

 are fully adult, but the teeth in some of the Chapada speci- 

 mens are a little more worn than they are in any of the 

 specimens of the Santa Marta series. None of them has the 

 sex indicated. 



One of the specimens of the Chapada series (No. 326) 

 presents an interesting dental abnormality, namely, a super- 

 numerary molar on the right side of the palate, situated op- 

 posite the junction of m 2 and m^, wholly internal to the 

 toothline. It has the crown structure of p 1 , but is larger, 

 about equalling p 2 . 



