240 MR. E. G. boulenger: r import on 



placed one of tliese traps, uieasaring 9| inches in lieight, in 

 various localities in the Gardens frequented by tlie rodents, but 

 without success. At a later date we found tliat this type was 

 being used with good results in a rat-infesved store, and on 

 comparing it with the one we had been using found that it differed 

 in measuring only 7 inches in height, and a similar one was 

 procured for our use. If not very successful it nevertheless 

 ■caught a number of rats, and obviously therefore, as was the case 

 with the Brailsford trap, it proved specially efficncious only 

 when conforming to certain measurements. With 124 traps of 

 this kind (7 inclies in heiglit) 12 rats weie captured. 



The ^^Mysto" Trap consists of a metal structure connected 

 with a tank full of water. The bait is placed just inside the 

 ■door, which closes on the entry of the rat. In order to effect its 

 escape the rat climbs up the cage to a hinged platfoi'ui, which 

 collapses, precipitating the rodent into the tank. The collapse of 

 this platform automatically opens the door of the cage and the 

 next rat is thus enabled to enter and repeat the performance. 

 Although I have been informed by some users of this trap that 

 it gave good results, the one which we tested for several weeks 

 Avas responsible for the capture of one rat only. 



A number of new types of cage-traps were sent us and given a 

 trial. Some were most ingenious, but as the}^ failed to catch 

 I'ats ic is unnecessary to allude to. them. 



It was found that several of the cage-traps we tested were 

 made of too light wire, with tlie result that the captured I'ats 

 were able to force the wires apart and escape. 



Barrel traps have frequently been asserted to be very effective, 

 and we tlierefore experimented with these both in the Gardens 

 and in other localities where rats were numerous. One of tlie 

 methods we employed was to fill the barrel up to within a foot of 

 the top with earth, covered with sawdust and chaff, and upon 

 this placed various bait. For some days we allowed the rats to 

 feed from the barrel. When we found that most of the bait had 

 been taken for several nights in succession, water was substituted 

 for the earth, also covered with a layer of sawdust and chaff; 

 and we awaited results. None were, however, forthcoming, the 

 rats obviously suspecting a deception. The other method con- 

 sisted of covering the barrel with brown paper, ujDon which the 

 bait was placed. After the food liad been taken for a few days 

 a cross was cut in the paper in order that the rats might fall 

 through into the barrel. This answered very much better, and 

 a number of rats were captured by this device. 



The ordinary Stockade trap consists of a wooden stockade 

 about 4 feet high constructed to enclose a space about 10 feet 

 square. On one side is a door a foot wide and high, which is 

 open and closed by a cord and pulley. The Stockade having 

 bee;i baited and the door kept open, the rats are for a week or so 

 allowed to feed and to run in and out. Subsequently the 

 operator secretes himself and at a suitable moment releases the 



