54 DESTEUCTR'E INSECTS OF VICTORIA 



exceedino;lv destructive to orano-e and lemon o;roves in 

 America and Australia. Professor Comstock {Report of 

 the Entomoloorisf^ U.S. Department of Agrimdture, 1880, 

 p. 295) records an instance in Australia where a grove of 

 33 acres, which in 1872 produced a rental of £1,800, 

 fetched in 1878 only £120, on account of the ravages of 

 this insect. 



In the very useful list published by Mr. Maskell we 

 find no mention of this species having attacked any plants 

 or trees but the orano;e and lemon. This is identical 

 With our experience in Victoria, for I have frequently 

 seen orange trees which were very badly infested with 

 this scale growing amongst shrubs of various kinds, and 

 on no occasion have I observed such to be visited by the 

 Red Scale as described above. Dr. M. Cooke (late Chief 

 Executive Horticultural Officer of California), however, 

 tells us that in California it has been found on gi'ape 

 vines and on the foliage of walnut trees, but gives it as 

 his opinion (always a valuable one) that but little damage 

 will be done to these j^lants by this pest. 



This insect, in common with others of this group, 

 increases very rapidly, and Dr. Cooke remarks that it is 

 thought by some writers that the females of this species 

 are viviparous. " I have," Dr. Cooke says, " watched 

 the female insect ovipositing, and immediately examined 

 the ^^^ or sac under a microscope, using a high power, 

 and could not detect any appendages ; however, in 24 

 hours I noticed the presence of antennae and legs. The 

 insect produces from two to four of these eggs or sacs in 

 24 hours, and the number produced by each female is 

 fi'om 20 to 43 ; the latter is the highest number I have 

 found." 



In Queensland Mr. Tryon, in his valuable book, states 

 that this scale, in the southern part of Queensland, also 

 attacks and kills the mulberry trees. I have seen other 

 kinds of scale on the mulberry trees here, but certainly 

 not this species. 



When this pest attacks a tree it may be easily detected 

 by the dirtv and stickv nature of the branches of the tree. 



