April 1907.] 



241 



Live Stock. 



On the sugar plantations, in the rough wooden buildings known as the 

 "bachelors' quarters," where the overseers lived, it was quite a common thing 

 to see a row of large green tree-frogs sitting along the wall-plate, or a more 

 friendly one sleeping on the washstand ; they were encouraged by the men, who 

 looked upon them as pets, from the fact that at night time they hunted all over 

 the place catching and devouring the large brown cockroaches. In the Flinders 

 River country a small Gecko lizard used to live in the walls of the men's hut, and 

 hunt cockroaches upon the root at night in a similar manner, but they were not 

 so smart as the coastal tree-frogs. 



Australia is rich in indigenous cockroaches, and in Kirby's " Synonymic 

 Catalogue of Orthoptera," vol. I, 1901, published by the British Museum, 217 species 

 are listed from Australia and Tasmania. 



Remedies and Methods op dealing with Cockroaches in the House. 



In ordinary cases, the different methods of poisoning are to be recommended. 

 Smith, in his " Economic Entomology," says that he has found equal parts of 

 powdered chocolate and borax, ground up thoroughly in a mortar, so that it is 

 well mixed, and placed in their runs, very effective in getting rid of the cock 

 roaches. Other writers advise the use of phosphorous paste, which is simply 

 sweetened flour paste, containing 2 per cent, of phosphorous ; this is spread on 

 bits of wood or cardboard and placed in all the sheltered corners where the roaches 

 congregate. During the last outbreak of plague, this mixture was distributed all 

 over Sydney as rat poison, but I believe it killed an immense number of large 

 American cockroaches wherever it was placed under the floors or cellars. 



Borax with many different forms of food is used, but Mr. Tepper has 

 recommended another method of inducing roaches to commit suicide. He first 

 places a saucer containing one part of plaster of Paris to four of flour, well mixed, 

 and close to it a saucer full of water, with a few sticks resting against the saucers, 

 so that they can easily get to the food and water. The roach becomes thirsty after 

 flour and plaster diet, and goes for the water, with the result that he gets small 

 bricks in his inside that kill him. 



An earthernware crock containing a few inches of stale beer, for which 

 cockroaches have a great liking, and then a few handy sticks resting against the 

 jar, so that they can climb up to get at the fluid, will often destroy great numbers 



The most successful method, where a large place is infested, is fumigation 

 with hydrocyanic acid gas, which, if properly applied, penetrates into every corner, 

 and suffocates big and little, most of them coming out of their hiding places and 

 dying on the floor, where they can be swept up in the morning and burnt, as where 

 the fumigation has been weak, it is sometimes found that the roaches revive. For 

 such fumigation, 1 lb. cyanide of potassium to a pint of sulphuric acid and three 

 pints of water will generate enough gas to poison 1,000 cubic feet of space. Bisul- 

 phide of carbon is sometimes used, but hydrocyanic acid gas has several advantages : 

 First, it is not inflammable ; secondly, it rises up on all sides, and is very volatile, 

 while bisulphide, being a heavy gas, sinks down, and if not used in sufficient strength, 

 will leave a stratum of unpoisoned air just where it is wanted most; and, lastly, 

 the vile smell of bisulphide will hang round for some time after the room has been 

 opened out, while hydrocyanic acid gas soon mixes with the air, and leaves no 

 smell of any consequence behind. Riley considers that burning pyrethrum, or 

 insect powder, will paralyse them, and even when it is simply scattered about on 

 the shelves or corners, or puffed into cracks and crevices, will soon clear them out ; 

 but its virture is but temporary, and it not only makes a mess on shelves and 

 cupboards, but is an expensive remedy in large premises. Paris green is another 

 very good thing to drive cockroaches away. It is scattered about or puffed into 



