26 First Report on Economic Zoology. 



may be bought. Nuinbers of these fruit trees are introduced and the 

 scales may be also l)rought over with the plants. If the scale is 

 seen the plants should be fumigated or destroyed. 



The Brown Currant Scale {Lecanium rihis) has also been found 

 on plum trees, especially in gardens when the trees are grown 

 against walls. 



Spkayers. 



For bush-fruit the best sprayers are the "Knapsack sprayers," 

 the " Eclair," the " Notus," the " Anti-pest," and others. 



Ordinary syringes are of no use in washing plants. The 

 insecticide must be sent out in the finest possible spray. 



Paraffin emulsion should be used first in April for currant scale 

 and repeatedly every two weeks for at least two months ; for 

 mussel scale in May, and likewise onwards. 



It is advisable to try caustic alkali wash alone for the first year. 

 This need not be put on by a " mistifier," as the object is to satm-ate 

 the tree, not to spread a fine even layer of the wash over it as when 

 Paris screen or emulsions are used. 



The Apple Bark Louse or Mussel Scale. 



(Mi/tilasjns pomorum, Linn.) 



Several correspondents of the Board of Agricultm^e have reported 

 damages to apple trees by the mussel scale, namely, from Eomsey, 

 Tarporley, Hayling Island, and other places previously mentioned. 

 One con-espondent thought the scale connected with thrips and 

 canker fungus. 



The best way to destroy this scale is to use the caustic alkali 

 wash in winter, and spray in the spring and early summer with 

 paraffin emulsion. 



A full account of this pest is given on page 75. 



Eggs on Apple Trees and a further Remedy 

 for Mussel Scale. 



(i) Apple shoots sent to the Board of Agiiculture from South 

 Norwood were covered with the eggs of (1) the Eed Spider {Bryobia 

 pruni), (2) the Apple Sucker {Psylla mali). The former are red 

 globular eggs, the latter are elongated o^'al and white. Two only of 

 the Psylla eggs could be detected. The majority of the Bryobia eggs 



