448 ON A SPECIES OF RAT INFESTING PORTION OF WESTERN N.S.W., 



informed by several rabbiters that they devour the young rabbits 

 caught in their ti-aps. For this reason and from the fact that in 

 many places more rats than rabbits are caught in the traps — 

 although the latter animals are nu.merous — they are held in 

 detestation by the rabbiters. When I left the Ivanhoe district 

 about the middle of May. the main body had passed on in a 

 southerly direction, but nuraei'ous stragglers still remained. On 

 my arrival here (Tilpa, Middle Darling) towards the end of that 

 month, I found them tolerably numerous along the river, and for 

 some shoi't distance out, but in the back country towards Cobar 

 they seem to be almost unknown. Within the last few days 

 (July 12th) I have returned from a trip in that direction, and I 

 find that they have become much more numerous along the river, 

 and spread further out. Whether this is another invasion taking 

 a more easterly direction than the preceding one, I am unable to 

 say. I notice here that, in addition to living in deep fissures, 

 masses of herbage, &c., they have constructed numerous burrows 

 as if they intended to remain for some time, and they have already 

 proved a great pest in the way of destruction to stores, &c. For 

 some months previous to their appearance at Ivanhoe I had heard 

 of their advance in a southerly direction from Western Queens- 

 land. At the time of their arrival on the Darling that river was 

 in high flood, and the water extended out for miles, but strange to 

 say this did not stop the onward march, for they soon appeared on 

 the opposite side, much to the grief of some rabbiters who, 

 thinking to pass off their skins for those of young rabbits, were 

 detected in the fraud, and sentenced to a long term of imprison- 

 ment. At the time of their appearance at Ivanhoe the Willandra 

 Creek — an anabranch of the Lachlan River — was also in high 

 flood, but this did not stop them ; and when I left they were in full 

 march for the Lachlan. In the year 1864 — a similar season to the 

 present — there was a similar invasion of rats throughout this same 

 country — the Darling being then in high flood — but although I 

 then saw numbers of them, after this lapse of time I am \inable to 

 say whether they were identical with the present species or not ; 

 though in one respect they certainly seem to difler, for in addition 



