58 DESTRUCTIVE INSECTS OF VICTOEIA : 



faith. It consists in boring a hole in the centre of the 

 stem of the tree and plugging it with either sulphur or 

 corrosive sublimate. I have, to please an old grower who 

 was very sanguine as to its efficacy, tried this for myself, 

 with the result which I had expected, viz., that the tree 

 after eighteen months has elapsed is just as bad as ever. 

 This recalls to my mind a remark by Professor Comstock, 

 who states it is claimed that the sulphur will be taken 

 up by the sap and carried to every part of the tree, 

 thus reaching and destroying every insect pest that 

 infests it. Apparently no account is taken of the 

 important facts that the sulphur is usually placed far 

 inside of the cambium layer, and consequently where 

 there is but little or any circulation of the sap, and that, 

 as sulphur is insoluble in water, it would not be taken 

 up by the sap even under the most favorable circum- 

 stances. 



So far we have not been able to discover any parasite, 

 at least in insects, which we could fairly look to to 

 exterminate this scale. From some experiments which I 

 have made, it was found that the JVovius, which has 

 worked such havoc amongst the Icerya, would not attack 

 this Red Scale. The other little insects also, as Crypto- 

 Icemus^ &c., &c., seem to make but little impression on 

 this scale, at least in Victoria. 



In America they are making most praiseworthy attempts 

 to introduce parasites of this kind, but from private 

 letters which I have received from that country it would 

 appear that but poor results have so far been attained. 

 Professor Riley, in some of his valuable publications, has 

 given the names of several insects which he hopes to be 

 able to use as auxiliaries in such cases, and our old. friend 

 Mr. Koebele is equally sanguine. We can only wish 

 them every success, and they can rely upon the assistance 

 of all Australian economic entomologists. 



Mr. Tryon, in his book, mentions a fungus — Microcera 

 coccopliila {Desm.) — and remarks — 



" This fungus, which really lives at the expense of the 

 Aspidiotus coccineus or Red Scale of Orange, is usually 



