NO. 1684; MAMMALS OF THE RHIO-LINGA ARCHIPELAGO— LYON. 433 



shorter naso-frontal suture. I can detect no differences between the 

 teeth of the two species. 



MeasiD-cments. — See table below. 



Specimens examined. — Five, all from Pulo Bulan. 



Remarks. — Ratufa hiilana is very closely related to R. insignis. 

 The skins of the type-specimens appear sufficiently distinct, but the 

 type of R. insignis is evidently in an unworn and unbleached jielage, 

 while the pelage of the series of R. hidana is much bleached. One of 

 the paratypes of R. insignis, Cat. No. 115532, U.S.N.M., is practically 

 indistinguishable externally from Cat. No. 144410, one of the para- 

 types of R. hulana. All of the specimens of the latter species, how- 

 ever, have the forelegs and thighs more russet than does the series of 

 R. insignis. The cranial characters serve to separate the two forms 

 instantly. 



External and cranial measurements of squirrels. 



a Collector's measurements. 



b Measured by writer after rela.xing feet in water. 



c Type. 

 d Defective. 



MUS ASPCR Miller. 



1900. Mus asper Miller, Proc. Biol. Soc. Washington, XIII, p. 145, Apr. 

 21, 1900. 



One specimen, skin and skull of an adult female, from Pulo Setoko. 

 This is- the second specimen of the Mus aspe?' group of rats known 

 from the Ehio-Linga Archipelago. The other is the type of JIus 

 hatannanus from Pulo Batam, which I wrongly referred in the orig- 

 inal description " to the Miis jerdoni group. A reexamination shows 

 it to be a member of the Mus asper group. The infrequency with 

 which rats of this group have been taken in the Rhio-Linga Archi- 

 pelago is surprising, in vicAv of their common occurrence on the Malay 

 Peninsula, Sumatra, Banka, and Billiton. 



For measurements of the Setoko specimen, see table, page 485. 



« Proc. U. S. Nat. Mus., XXXI, No. 1502, p. 654, January 16, 1907. 



