10 



Mr. W. E. de Wiaton on 



of f rentals 21*5; interorbital constriction 12'1 ; length of 

 nasals 14 '5 ; greatest breadth of nasals 6 ; basal length 42 ; 

 gnatliion to back of palate 21*5 ; back of palate to foramen 

 magnum 17'5; length of incisive foramina 4; diastema 12; 

 upper molar series 9; outside molars 11 ; length of auditory 

 bulla 10-5. 



Mandible : length (bone only) 28*5 ; back of incisors to 

 coronoid 25'3, to condyle 28*5, to angle 25 ; greatest height 

 16 ; lower molar series 9. 



Type ((?), British Museum no. 98. 5. 4. 9. Teeth worn. 



Collector G. L. Bates, no. 315. Fang name " Kwe." 

 Benito E-iver, 15 miles from mouth, 6th Jan., 1898. 



Specimens of different ages and sexes killed from September 

 to January do not vary in colour. 



The chief interest in this squirrel is due to the fact that 

 the molars have a more complicated pattern than is found in 

 any of its near allies. The accompanying figures will show 

 the pattern of the molars of some of the group. Fig. 3 repre- 

 sents R. ^ of F. mystax ; it will be seen that there is an 

 extra infolding of the enamel on the outer side ; the central 



Fis:. 1. 



Fiff. 2. 



Fis. 3. 



Fio;. 4. 



of Funisciurus anerythrus. 



Fig. l.-R. 



Fig. 2. — Ditto of J^. pyrrJiopTis, 

 Fig. 3. — Ditto of F. mystax. 

 Yig. 4. — Ditto of F. Jacksoiii. 



cusp is only rudimentary in the majority of the existing 

 squirrels, but is found in Anomalurus and in some fossils 

 which are not considered to belong to Sciurus, and it is not 

 too much to say that had this tooth been found in a fossil 

 slate it would not have been referred to a true squirrel. 



Four specimens examined have teeth of precisely the same 

 pattern ; and I think it will be interesting to palaeontologists 

 to have an accurate figure recording the occurrence in an 

 existing species. 



Although the teeth of F. pijrrhopus and F. anerythrus have 

 been figured before in Dr. Forsyth Major's most valuable 

 paper in the P.Z. S. 1893, pi. viii., I have thought it advisable 

 to reproduce them in a similar manner to that of F. mystax 



