658 Bulletin American Museum of Natural History [Vol. LXVI 



manner. Thus specimens from the Kasai and from Angola appear to 

 have longer hair which carries less pigment than that in all but a few 

 individuals from the northeastern Congo, and this same tendency is 

 indicated by some of the ten scattered specimens from the Guinea coast 

 which have come into my hands, though these specimens are too few 

 and too closely approximated by specimens in the Congo Expedition 

 series to warrant recognition of races within the species. 



Collector's Measurements 



Total Length Tail Length Foot Length 



52 <?, 9 777.9 (617-1027) 463.4 (350-607) 57.1 (45-75) 



25 c? 793.2 (617-1027) 469.6 (360-607) 58.0 (45-75) 



25 9 768.4 (630- 920) 460.4 (350-590) 56.4 (45-75) 



Cranial Characters. — Individual variation in the skulls of tri- 

 cuspis is localized and does not approach the extreme variation in general 

 form found, by contrast, in our much smaller series of longicaudatus. 

 The features of tricuspis subject to most pronounced variation are the 

 nasals, the lacrimals, and the foramina. The nasals vary most strikingly 

 in the form of their lateral wings. These are occasionally bilaterally 

 asymmetrical, as, for example, in one specimen in which the suture sep- 

 arating the right and left nasals is neither straight nor in the median 

 plane. The lacrimals are in some specimens totally within the orbit, 

 while in others they extend far forward between the frontal and maxillary. 

 They are in some skulls high above the zygomatic processes of the maxil- 

 lary and in others extend outward and downward to take some part in 

 its formation. The foramen magnum and all of the smaller foramina 

 present a wide range of variation in size and form. 



Age variation presents no peculiar features in the species. Unlike 

 the condition in gigantea, but in agreement with that in longicaudatus, 

 the sutures of the roof and sides of the cranium seem never to fuse to the 

 extent of obliteration of the sutures, though they are tight throughout 

 the period of adult life. 



The four occipitals unite early to form a single bone. 



The suture of the basal components of the cranium unite in this 

 sequence from the rear forward: basioccipital-basisphenoidal ; basi- 

 sphenoidal-presphenoidal. Other sutures seem never to close. Even in 

 the oldest skulls the sutures of the palatal region are widely open. 



Sexual differentiation appears not to have occurred in the skulls 

 except with reference to size. As may be seen from an examination of the 

 table of cranial measurements, the males exceed the females in size, as 

 they do in the other African pangolins. 



