160 RATS AND PLAGUE. 
due to his total non-acquaintance with the group of non-rattus 
rats with bicolored tails and spiny coats; and to failure in 
erasping the fact that these animals are never found in towns. 
He thus mistakes for these latter the sports which occur so 
frequently amongst the rattus group. 
The author’s faulty knowledge of the Eastern portion of the 
genus Mus isillustrated by thestatement (p. 9) that “ over ninety 
species of rats have been described from the oriental region 
which are indisputably closely allied to Mus rattus.” This is a 
decided error: less than one-third of the names in the list he 
refers to, including synonyms, can be attached to animals of. 
the rattws group, and the remainder are nearly all those of 
members of groups whose centres of distribution are outside the . 
Indian sub-region altogether—if the rural areas therein have 
been thoroughly worked,—and on its borders are represented 
by very few species only; i.e., Maus gerdont and perhaps Mus 
niveiventer from the Himalayas with Mus bowers: from Mani- 
pur and Yunnan, and Mus berdmore: from Manipur Tenasserim. 
On p. 10, Mus jerdoni is rightly excluded from the rattus 
group, yet on pp. 93 and 94 it is claimed © on sure evidence” as 
one of four established races of the rattus type.” The reason 
for this laying down of the law seems to have arisen from the 
fact that several animals with bicolored tails—evidently 
abnormal examples of Mus rattws—were caught in houses in 
Naini Tal and—because of their albinistic traits—regarded as 
example of Mus jerdont. Had it been understood that this 
latter with many others of its type is a rat of purely rural 
habitat, such confusion would have been impossible. 
The bicoloration of the tail is not, as is stated on p. 89, 
“the all-important feature in the description of many species 
of the vattus group,” but it is of secondary importance in des- 
criptions of non-rattus species and in separating these latter 
from the others. Normal vattus rats do not have bicoloured 
tails, though Mus vicerex, Bonhot, appears to be an exception. 
The bulk of the paper is concerned with descriptions of 
the rats obtained in the towns of India in connection with 
plague investigations but its value is largely obscured by the 
Jour, Straits Branch 
