1094 



THE BOOK OF GARDENING. 



but more especially to Damsons, Plums, Gooseberries, &c. Not 

 only does Red Spider injure its host-plants by continually sucking 

 the juices from the foliage, but the web that it spins prevents 

 the leaves from exercising their proper functions. The spinning 

 apparatus is very well shown in the ventral view of a Red Spider 

 illustrated at Fig. 706. The pest increases rapidly, and in very 



bad attacks the foliage assumes 

 an unhealthy, yellow, blotched 

 appearance, and falls. Paraffin 

 emulsion is one of the best 

 remedies for outdoor plants, and 

 this should be repeated until all 

 the pests are removed. 



Indoors on Grape-vines the 

 XL All Vaporising Insecticide 

 should be resorted to. Many 

 gardeners trust to sulphur in 

 the evaporating-troughs or on 

 the hot-water pipes, but this will 

 not get rid of the pests. A dry 

 atmosphere is conducive to Red 

 Spider attacks, and the aim, 

 therefore, of the grower must 

 be to see that there is plenty of 

 atmospheric moisture at the out- 

 set. If the Spider should appear 

 in the early part of the season, 

 syringing with clear rain-water 

 through an elbowed nozzle will 

 be productive of much good. 



Sawflies are only destructive 

 in the larval, or caterpillar, stage 

 — a stage in which they are often mistaken for Moth or Butterfly 

 larvae, though they differ from the latter in possessing a larger 

 number of legs. They are chewing insects, and affect a variety 

 of outdoor plants — Turnips, Apples, Pears, Nuts, Currants, Goose- 

 berries, &c. Though their presence is soon betrayed, yet insects 

 like those affecting Gooseberries are difficult to see, so closely 

 do they approximate to the colour of their food-plant. The 

 insects feed sometimes enclosed in a web like Pamphilius flavi- 

 ventris, a common pest of Pears ; curled up in the leaves of 

 their food-plant, like Cladius pyri, which infest the Plum and 

 the Pear; or exposed like the Nut Sawfly (Crcesus septentrionalis). 

 Then their manner of attack varies. With some species it is 

 usual to commence with the edge of the foliage ; with others it 

 is the epidermis only which is involved. All the common kinds 

 enumerated are best poisoned through their food-plant, while 

 as an additional precaution the soil beneath the trees may be 



Fig. 706. — Ventral View of a 

 Red Spider. 



(magnified 130 diameters.) 



