NO. 1502. MAMMALS OF BA TAM ISLAND— L YON. 655 



wider, the posterior edge of the palate more emarginate, and the 

 interorbital region is slightly heavier. 



^lea-surenient.v of type. — Total length, 267 mm.; head and body, 148 

 tail, 129; hind foot, without claws, 31; greatest length of skull, 3().3 

 basal length, 30.5; condylo-basal length, 34.5; z3^gomatic width, 15.3 

 interorbital constriction, 6.5; maxillary tooth row (alveoli), 6.2; man- 

 dible back of condyle to front of symphysis, 19.7; mandibular tooth 

 row, 5.9. 



Specimens examined. — One, the typo. 



MUS LINGENSIS Miller. 



1906. Mm Ibujensis Miller, Proc. II. S. Nat. Mus., XXXI, 1906, p. 266. 

 One skin and twelve skulls collected at Senimba Bay in September, 



1905, and eight skins and skulls March and April, 1906. This series, 

 as a whole, is exactly like a series of topotypes from Linga. This 

 species shows much variation in the size of the skull. In the series 

 from Batam, the greatest length of the largest skull. Cat. No. 143217, 

 U.S.N.M., with teeth considerably worn, is 48.3 mm., while in Cat. 

 No. 143221, U.S.N.M., a skull in every way adult, with teeth slightly 

 worn, the same measurement is 42.5 mm. Similar differences in size 

 are found in examples from Linga. 



MUS sp. near RATTUS. 



1906. Mus near rattns, ]\Iiller, Proc. V. S. Nat. Mus., XXXI, 1906, p. 266. 



Four specimens taken September, 1905, and twelve taken in March 

 and April, 1906. This rat is extremely variable. The series of 

 skins falls into two groups — those with bellies nearly white, like speci- 

 mens of 3£usjarak Bonhote, from southern Johore, and those with dirty, 

 buffy-gray bellies, much like a specimen of Mus griseiventer Bonhote, 

 from Johore. Some individuals are nearly intermediate between these 

 extremes of coloration of the under parts. As great differences are 

 found in the color of the upper parts, some individuals being colored 

 like a small Norway rat, while others are nearly as dark as a black 

 rat. As a rule, those specimens darkest above are lightest beneath, 

 but there are exceptions. The skulls also show many inconstant 

 variations. 



MUS FIRMUS Miller. 



Three adults, skins and skulls, collected at Senimba Ba}^, March, 



1906, do not differ from topotypes of this species from Linga. 



ARCTOGALIDIA SIMPLEX Miller. 



1906. Arctogalidia simplex Miller, Proc. U. S, Nat. Mus., XXXI, 1906, p. 268. 

 An adult female taken in September, 1905. 



