NO. 2188. MAMMALS FROM ISLANDS OFF SUMATRA— LYON. 445 



Slcull and teeth,. — Skull large and long, with long, slender rostrum, 

 bullae of moderate size; not unusually small or large, maximum 

 length 11 mm., teeth large and heavy, maxillary toothrow 12.5; 

 maximum width of toothrow, 3.2. 



Measurements.— Tj^e: Head and body, 230 mm.; tail, 130; hind 

 foot, 45; condylobasal length, 53.8; zygomatic width, 28.3; width of 

 braincase, 23; interorbital constriction, 13.4; maximum length of 

 nasals, 22; maxillary toothrow, 12.5. 



Specimens examined. — One, the type. 



Remarlcs. — RMnosciurus incultus is not a highly characterized form, 

 and is here described as new largely because of inability to assign it 

 to any of the numerous named forms of the original Sciurus laticau- 

 datus. Material in the United States National Museum for making 

 comparisons of this group is extremely meager, and the descriptions 

 of some of the forms are lacking in detail. As nearly as can be made 

 out from the descriptions the following are the characters of the other 

 members of this group. 



Laticaudatus, Borneo, light colored animal, with moderately large 

 skull, rostrum and bullae. 



Tupaioides, Singapore and Malay Peninsula, tail washed with 

 white instead of buffy, belly white, flanks buffy. 



Rohinsoni, Tioman Island, tail washed with buffy, bullae smaller 

 than in laticaudatus, and much smaller than in tupaioides. 



Peracer, Perak, Malay Peninsula, tail washed with buffy, relatively 

 small bullae, about as in laticaudatus. 



Leo, Singapore, and Malay Peninsula, like peracer, but brighter 

 colored, and with very large bullae, distinguishing it from all the 

 others. 



Leo rUonis, Karimon, Kundar, Batam, and Bintang Islands, Uke 

 lea but with better shoulder stripes and more buffy underparts. 



RATUFA PALLIATA BATUANA, new subspecies. 



1908. Ratufa polliata, Lyon, Ann. Mag. Nat. Hist., eer. 8, vol. 1, p. 137, Feb- 

 ruary, 1908. 



Type-Specimen. — Skin and skull of adult male, No. 121707, U.S. 

 N.M., collected on Tana Bala of the Batu Islands, February 11, 1903, 

 by Dr. W. L. Abbott; original number 2263. 



GeograpMc distribution. — Known only from Tana Bala and Tana 

 Masa of the Batu Islands. 



Diagnostic cJiaracters. — A form of R. polliata characterized by its 

 smaller size and in the possession of polliata type of nasal and pre- 

 maxillary, and not of the laenata type; that is, the posterior end 

 of the nasals and of the nasal branches of the premaxiUaries he on 

 about the same straight hne and the combined anterior median pro- 

 jections of the maxillaries, not unusually narrow. 



