366 PROTECTION AGAINST INSECTS. 



termed Chcrmes stroll, Htg., attack plants from five years old 

 and mature trees. Young plants become greatly weakened by 

 these attacks, and many Weymouth pines have thus been killed 

 in the Woburn Woods, Bedfordshire. 

 Remedial measures, as before. 



FAMILY II. COCCIDAB (SCALE-INSECTS). 

 Description of Family. 



Very minute insects with moniliform antennae, of 6 to 25 

 joints ; rostrum rudimentary in the $ . $ with 2 or 4 mem- 

 branous wings without cells ; ? , except one apterous species, 

 Aleurodes chalidonii, Latr., swollen, more or less shield-shaped ; 

 one tarsal joint. The $ burrow their beak deep into the plant- 

 tissues and swell up into spherical bodies, and in May and 

 June lay numerous eggs on plants, and die on the eggs. The 

 eggs hatch into $ and 2 larvae that pupate in autumn or spring. 

 Single generation. 



The imagos and larvae, under the protection of shields or 

 puparia, partly composed of fibrous secretion, partly of the 

 cast-off exuviae, suck the young shoots, leaves, bark, etc. of 

 perfectly sound plants, and cause blistering and disease in the 

 organs which they have attacked. In this way, beech, spruce, 

 oak, ash, robinia, and other plants may be attacked by different 

 species. 



The most effective treatment known for nursery plants so 

 attacked is to wash them with limewater in the spring, or cut 

 off and burn infected twigs. The plants may also be treated, 

 when practicable, with paraffin emulsion or washes made by 

 forming a soap with boiling water, resin and potash. The 

 scales may also be scraped off with a blunt knife, or rough 

 brush, and the plants smeared with soft-soap and water.* 

 When scale appears on coppice-shoots or saplings, cut and 

 burn the affected plants. 



1. Coccus fagi, Biirensp. (Scale-felt, or Beech woolly aphis). 



Hitherto only the ? is known. This is a very small, pale- 

 yellow, legless, apterous scale-insect, measuring about ^ inch 



* For apple-scale Miss Ormerod recommends 2 Ibs. soft soap, 1 Ib. flowers of 

 sulphur, 14 gallons of water. 



