82 JOURNAL, BOMBAY NATURAL MIST. SOCIETY, Vol XXVI. 



rats more frequent in the latter, both types occur together in each 

 locality : — 



Head & 



Body in 



mm. 



No. of 

 speci- 

 mens. 



7oOf 



H. & B. 

 formed 

 by tail. 



Hoshangabad. 



Chanda. 



100-1 29-22-2-1 6-6 

 100-130-20 -15 2 

 100- -20-3-15-7 

 100-139-21 -3-11-9 

 100-123-18-1-13-8 



3 



7 

 7 

 1 



100-149-22-1-15-7 

 100-146-21-2-15-2 

 100-1 35- 20-4-14-7 

 100-141-19-1-14'2 



On comparing this table with that given at p. 75 it will be seen 

 that the white bellied R. r. narhadce, as regards tail length, appro- 

 ximately represents the mean between the long-tailed and short- 

 tailed, dark- bellied types just discussed. 



In the quality of the pelage and in the dorsal colour these dark- 

 bellied rats are very similar to the typical white bellied B. r. 

 narhadoi ; possibly the general tone of the backs is a little 

 darker and greyer. The grey flank colour merges insensibly into 

 the dusky tint of the belly. The ventral hairs are slaty through- 

 out the greater part of their length, but their extreme tips are 

 frequently yellowish and impart a very characteristic rusty tinge 

 or bloom to the undersurface ; this rustiness and the roughness of 

 the ventral siu'face is very different in appearance from the bluish, 

 sleek belly of R. r. ratlus. Pale yellow or dirty white chest spots are 

 not infrequently pi^esent. The feet are usually dusky brown above. 



As will be seen from Tables I and II the skull agrees veiy 

 closely in size and proportions with that of typical narhadce ; and 

 I am quite unable to distinguish them. 



Remarks : — I have had a good deal of difficulty in making up 

 my mind as to the status ot the rats of the Central Provinces, but 

 after considering the facts in connection with what is found else- 

 where, e.g., in Kathiawar, it seems difficult to avoid the conclusion 

 that in this district the dark bellied form is merely a parasitic 

 development from the local white bellied race. With the acquisi- 

 tion of parasitic habits the stock seems to have become richer in 

 pigment, and the tail length has alternatively been either greatly 

 increased or greatl}^ diminished. No change in the head muscles o^; 

 skull has as yet been brought about. But the wild and the parasitic 

 stocks are still mingled together in each locality; and doubtless 

 each reacts on the other. Tn this probably lies the explanation 



