300 Modern Lnprovements in Horticulture, 



tion, "and it may be otherwise offensive to them. They are 

 imperceptible to the naked eye when very young, and it appears 

 they can even insinuate themselves under the bark: before 

 they bring forth their young they become stationary, and con- 

 struct for themselves nurseries for that purpose, composed of 

 some exuviae from their bodies, which are formed into a brown 

 hemispherical shell, as on orange trees, pines, ash, &c., or into 

 an efflorescent fibrous covering, (hence lanigera,) as on apple, 

 larch, and Weymouth pine, &c. 



Caterpillars. — The larvae of butterflies, moths, beetles, and 

 innumerable flies, infest and devour the leaves, flowers, and 

 fruit of vegetables, requiring the unceasing vigilance of the gar- 

 dener. The snail tribe are also a voracious pest, and being 

 oviparous hermaphrodites, increase very fast, delight in damp 

 places and damp weather. Salt or powdered quick-lime kills 

 and disperses them. 



The disfiguring effect of insects upon trees is generally 

 called blight, and is by some naturalists attributed to certain 

 noxious qualities of the air or winds, but it is perhaps more 

 rational to conclude that inherent disease and insects are the 

 most prevalent causes. That the leaves and tender shoots of 

 plants are often damaged by frosty, accidental noxious, or 

 parching air, is too often seen, and such effects are properly 

 called blight ; but the depredations of insects are quite another 

 thing, and therefore should not be confounded therewith, lest 

 the idea may throw the gardener off his guard by passively suf- 

 fering under what is conceived to be an atmospherical, and 

 therefore an irresistible agent, instead of inspecting, detecting, 

 and driving the lurking and tangible enemy from their hold. 



Almost every gardener is acquainted with some means or 

 other of getting rid of insects as soon as their depredations are 

 visible, but the desideratum is, the prevention of their attacks 

 rather than the cure of them ; this should be the cultivator's 

 object. For this purpose he should be acquainted with the 

 economy of the insects, so as to be able to ascertain or guess 

 where and how they subsist through the winter ; how they in 

 their egg state may be vulnerable to liquid or pulverised appli- 

 cations. Many, and perhaps simple compositions may effect 

 this, if only applied from a watering pot or puff, before, or at 



