MAMMALS FROM MENTAAVEI 661 



rity they show. For of twenty species, of whicli eig-ht are bats 

 and two (Macacus, Mus raltus) may have l)een of human impor- 

 tation, no less than five , that is to say lialf of the indigenous 

 terrestrial species, are altogether peculiar {}), four being new. 

 And even of the other five, two {Paradoxurus sp., Sciuroplerus 

 aurantiacus?) are only referred to older species provisionally, 

 owing to Dr. Modigliani's specimens of them being immature or 

 otlierwise insufficient for proper determination. There are there- 

 fore only left three non-volant species ( Tupaia ferruginea hijpo- 

 chrysa, Pteromys nitidus and Mus rajah) which are referred with 

 any confidence to forms known elsewhere, and it may be noted 

 that two of these three are common and widely distributed 

 Malay animals, the other being Javan. 



Two things about the peculiar species are worthy of note. 

 One is how very distinct they all are from forms known else- 

 where, no one being only barely distinct; indeed, far from there 

 having been any difficulty in distinguishing them , the puzzle 

 has rather been to find species to which the four new ones 

 might be suitably compared for diagnostic purposes. 



The second point is the great prevalence of sombre colouration 

 among them, a characteristic here attained entirely without any 

 mixture of the melanism commonly so frequent in insular areas. 

 The Sciuroplerus is wholly dark l)rownish black, Sciurus mela- 

 nogaster is unique in having a black belly, S. fraterculus is a 

 very dull coloured species, as is Mus siporamis, while the Semno- 

 pithecus, belonging to a group in which the normal colour is 

 brightly contrasted grey and white, has done its best in the 

 same direction by darkening its back and tail to black and its 

 belly to dark rufous, even though it has still retained the white 

 head and genital markings. 



With the exception of a few passing references by earlier 

 authors, our whole knowledge of the Mammalogy of the chain 

 of islands running parallel with the west coast of Sumatra is 



(') On tlie assumption that the Tenasserim locality of Scmnopithecus potetLCiani 

 IS erroneous, see below. 



