SPO ee Le 4} 
204 THE AUSYRALIAN NATURALIS!. 
aspera) was very abundant, and M. decamanus, to which all my 
chservations refer, used to devour quantities of them; lke apex 
of the shell was always bitten off so that the molluse could be 
readily extracted. _On the upper Waikato River, New Zealand, 
the same rat dives into the water and gathers the fresh water 
Unio, which it gnaws open end eats. The shells ure always 
gaawed through at the same spot of one valve, but I ferget now 
whether it is the right or left one. 
The well-known “Bugong” or “Bogong” moth at times invades 
our cities and comes into houses, stores, &c., for darkness and 
shelter. At Melbourne I have cbserved the rats in a large sugar 
store collect the moths and eat the bodies, rejecting the wings. 
I recently observed a case of a somewhat curious article of diet 
_for a rat. For a number of months a rat which frequented the 
laundry attached to my house, made a practice of eating soap. 
Pieces of ordinary bar soap used for washing clothes, ieft lying 
about, were taken to sheltered corners and there consumed. <A 
specimen exhibited shows the marks of the rat’s teetn. After 
many attempts, I succeeded in trapping the rat, which proved to 
be a young’ male of the common brown rat (M. decamanus) . 
The exereta left by the animal was always quite normal, so I 
conclude that it must have got cther food besides the svap, but I 
have been quite unable to trace its mode of ingress and egress 
from the laundry, as I could not find holes or openings of any 
kind, and no food was ever kent there. 
It may be of interest to deseribe the trap by which, after 
many attempts with other devices, I was able to catch the rat. 
A spring trap was set open in a box with a piece of tissue paper 
over the jaws, and the whole completely covered, paper and all, 
with bran, and a piece of fresh fish placed at the far end of the 
box. The lid had an opening cut just above the jaws of the 
trap, so that when the rat entered the trap was sprung and the 
visitor captured. On examination I found its stomach gorged 
with fresh bran, which it had scooped up before entering, but the 
intestines were practically emvty. 
