LECANIUM HESPERIDUM. 101 



The injury -which is caused by this Orange Scale is, 

 firstly, by the Scale insects drawing away the juices of 

 the leaves (or whatever part they attack) with their 

 suckers, by which they waste the sap and also injure the 

 state of the tissues by pricking them with numbers of 

 little holes ; and, secondly, by the shoots (if badly 

 attacked) becoming covered with masses of black 

 filth. 



In the case of some Scale-infested Orange or Lemon 

 shoots sent over to me from California for examination, 

 they were fairly smothered in the masses of Scales and 

 black dirt. It is thus described in a short, clear, and 

 spirited paper by Prof. MacOwan, Director of the Cape 

 Town Botanic Gardens, on " Diseases of Orange Trees, 

 Scale, &c."* : 



" When the Scale is only moderately present the tree 

 keeps a-head of the injury, but if there be much of it, 

 so that the Coccus' sugary excrement varnishes over 

 the leaves, then there will come a detestable black 

 fungus (Capnodium Footii), growing on the saccharine 

 secretion and choking up the stomata or breathing-pores 

 of the leaves. Now for this plague there is nothing to 

 be done but cleaning down with alkaline and soapy 

 syringings." 



With regard to applications, probably any soapy or 

 other wash would answer the purpose which would stifle 

 or kill the Scales, without risk of damage to the leafage 

 or fruit beyond what might be prevented by a " swilling" 

 with clean water afterwards. 



At pp. 79 86, in the preceding paper on Australian 

 Bug or Soft Cushiony Scale, are various recipes which 



that it was the male of L. hesperidum (be what it may it came from under 

 the L. hesperidum Scale, and I fortunately preserved the mounting." 

 Injurious Insects of the Orchard, Vineyard, &c.,' by Matthew Cooke, 

 late Chief Executive Horticultural Officer of California (Sacramento, 

 Cal. U. S. A. 1883), pp. 164, 165. 



* Paper on " Diseases of Orange Trees, the Scale, &c.," by Prof. P. 

 MacOwan, F.L.S., Director of the Cape Town Botanic Gardens; in 

 ' Agricultural Journal,' published by the Department of Agriculture of 

 the Cape Colony, No. 14, 1888, pp. 1, 2. 



