mam:mals collected by dr. w. l. abhott 219 



breadth between tips of postorbital processes 27.4 (34) ; zygomatic 

 breadth 3 1 (37) ; mastoid breadth 21.4 (25) ; breadth of palate between 

 premolars 6.S (S.4) ; depth of rostrum at posterior extremity of nasals 

 12.S (13.6) ; mandible 31.4 (37) ; depth of mandible at posterior root 

 of large premolars S (9); maxillary toothrow (alveoli) 10 (11); 

 breadth across both upper incisors together at rim of alveoli 5 (6) ; 

 mandibular toothrow (alveoli) 10 (11.4). 



Specimens exatnl?icd. — Two, both from the type locality. 



Remarks. — Sciunis tjiimelhis is distinguished from S. prcvostil, 

 aside from its size, by the reduction in width of the white lateral band. 

 In the mainland animal this band is so wide that on the hind leg it oc- 

 cupies the entire outer side, reducing the black to a mere inconspicu- 

 ous line between it and the red. In S. mimellus on the other hand 

 the white occupies rather less space on the leg than the black, so 

 that the latter color is more conspicuous than the white when the skin 

 is A'iewed from above. Six adult specimens of Schiriis prevostii 

 from Trong, Lower Siam, measure: total length, 533 (502-553); 

 head and body 262 (24S-273) ; tail vertebrae 275 (254-286); hind 

 foot 62.5 (60-65) ; hind foot without claws 58 (56-60). 



SCIURUS MIMICULUS sp. nov. 



Type. — Adult male (skin and skull). No. 101616 United States 

 National ]Museum. From Ste. Barbe Island. Collected August i, 

 1899. 



Charactei's. — Similar to Sciurus mifnellus but even smaller (hind 

 foot about 40, greatest length of skull about 48). 



Color, — In color Scizirzis mimiciihis exactly agrees with S. mimel- 

 lus^ even to the narrowing of the white lateral band and consequent 

 increase in the amount of black on the hind leg as compared with S. 

 prevostii. 



Sktill. — The skull (fig. 12, a) is as in Sciurus mim,ellus, though 

 much smaller. Audital bullae slightly less inflated than in the larger 

 species. 



Measurements. — External measurements of type: total length 381 ; 

 head and body 203; tail vertebrae 178; pencil 50; hind foot 42 (38). 

 Average of nine specimens fi'om the type locality : total length 387 

 (375-406); head and body 198 (191-203); tail vertebrae 189 (17S- 

 203) ; hind foot 43.5 (42-49) ; hind foot without claws 42.4 (38-45). 



Cranial measurements of type : greatest length 48 ; basal length 41 ; 

 basilar length 38; palatal length 20; length of nasals 14; breadth 

 of nasals anteriorly 7 ; breadth of nasals posteriorly 5 ; interorbital 



