466 



Journal of Agriculture , Victoria. [lo Aug., 191 2. 



The eggs, pinkish in colour, are very minute, and hard to (Hstinguish. 

 The colour and appearance of the scales vary through the different stages 

 of their life history. The young insects that have just hatched out have 

 also a pinky, somewhat transparent a])pearance. As the .scales begin to grow 

 they assume a vellowish colour with darker markings ; gradually, as they 

 mature, they become grey, brown, and black, and vary considerably in 

 size, some of the adult insects being c]uite large. 



The adult female usually occupies the whole of the space under the 

 shell-like covering, but when egg-laying begins — and it continues for some 

 time — a gradual diminution takes place in her size, until there is practically 

 nothing left but a filament of skin, the eggs occupying the whole of the 

 space under the covering. 



With regard to the number of eggs laid by an adult female, some 

 difference of opinion appears to exist, between 200 and 300 are said by 

 some authorities to be about the average. In observations on this point 



FIG. 21. -BLACK OLIVE SCALE (MAGNIFIED). 



carried out by the writer, the number of eggs found under each scale was 

 much greater. In no case, in fact, was the number less than 700, and in 

 the greater number of cases noted considerably oxer 1,000 were found. 

 It must be stated, though, that all examined were well-developed specimens, 

 living somewhat isolated from others. Probablv the number of eggs found 

 under the average scale shell, where they are crowded together, would be 

 much less, and would more likely approximate the numbers first mentioned. 

 However this may be, it is certain that this insect is fairly prolific, and 

 will soon spread if left unmolested. 



The usual methods of combating this pest, and those of a similar kind, 

 are by spraying or fumigation. In spraying petroleum compounds are 

 most favoured ; they are cheap, easy to prepare, and, if properlv applied, 

 effective in reducing the pest. 



Red oil, crude petroleum oil emulsion, and kerosene emulsion are all 

 prepared in the following way : — Boil i gallon of water and 1 lb. of 



