THE PEAR. 



469 



young chermes may be easily brushed off the 

 leaves by means of a painter's brush, and, as 

 they fall to the gi-ound, destroyed by treading 

 upon them. The winged insect may be cap- 

 tured during May, their red colour rendering 

 them distinguishable to the eye. 



Aphis pyri-mali, the pear-and-apple aphis. 

 That the pear and the apple have each a, dis- 

 tinct species of aphis peculiar to themselves ia 

 believed by some ; a large majority, however, of 

 entomologists consider the aphis found on both 

 these trees to be identical, and hence the name 

 Aphis pyri-mali. However this may be settled 

 by men of science, it is quite enough for all 

 practical purposes to consider them the same. 

 Those species of the genus Aphis, plant-louse, 

 green-fly, black-fly, &c., which are destructive to 

 fruit trees, are too well known to require' a 

 lengthened description of their forms and trans- 

 formations. It may be sufficient for our pur- 

 pose to glance at their mode of attack, and offer 

 the best methods for their suppression or de- 

 struction. They do not eat up the leaves of 

 trees and plants like many caterpillars, but they 

 insert their rostrums into the leaves, and suck 

 up the sap, causing the leaves to wither and fall 

 off, and, consequently, greatly enfeebling the 

 tree, if they do not kill it altogether. They 

 appear as early in spring as the first develop- 

 ment of the tender leaves, being produced from 

 eggs laid on the branches the previous autumn, 

 and consist entirely of females, destitute of 

 wings ; and these are no sooner brought into 

 existence than they begin their work of de- 

 struction. In about ten or twelve days this 

 earliest brood begins to produce young, which 

 appear to be females also, and, like the former, 

 destitute of wings. In about ten days after- 

 wards, this second brood produces a third 

 brood; but, unlike the former, this latter has 

 in it both winged and wingless females, and the 

 same production of both winged and wingless 

 insects takes place in several succeeding genera- 

 tions to the extent of about sixteen, some say 

 twenty, generations annually. The insects of 

 the third generation that have wings quit the 

 tree on which they were hatched when of 

 mature size, and seek out for themselves other 

 trees on which to feed and propagate their 

 species, the wingless ones remaining on the 

 tree on which they were bred. Towards the 

 middle of September, males and females are 

 produced, at which time the last generation 

 for the season is produced. The apple-and- 

 pear aphis, Kollar remarks, produces the 

 males without wings, while the peach aphis. 

 Aphis persicce, produces them with wings: he 

 also observes, " When these newly-born males 

 and females have attained their full size, pairing 

 takes place. The females then no longer pro- 

 duce living young ones, but lay eggs, from which 

 the mothers of the forthcoming generations 

 proceed. They do not, however, lay their eggs 

 on the leaves, because these would fall off, and 

 the eggs lying on the ground till spring would 

 be destroyed ; but they lay them on the twig 

 or shoot itself, and either all around it, like the 

 apple aphis, or on the buds, or near them, like 

 the plum-and-peach aphides, the latter some- 

 VOL. II. 



times laying their eggs on the matting with 

 which the twigs are fastened to an espalier in 

 summer. The females, having thus provided 

 for their future spring progeny, die off by de- 

 grees in the autumn. The eggs have now only 

 the winter to endure, which never kills them, 

 however severe and changeable it may be." 

 The natural enemies of the aphis are the 

 larvas of syrphideous flies, or those of the 

 ladybird beetles, figs. 14 and 15, which are 

 nourished chiefly on the aphides. The ant 

 is said by some to be attracted to the locality 

 of the aphis by the sweet fluid ejected by the 

 latter, and that they feed only on it ; our own 

 observation is, that they not only feed on this 

 ejected excrementitious matter, but that they 

 devour the aphides themselves in inconceivable 

 numbers. ■ Birds also aid in devouring them. 

 The eggs of the apple-and-pear aphis may 

 readily be rubbed off the shoots on which they 

 are laid during autumn and winter; they are 

 easily seen lying close together like grains 

 of gunpowder. Washing or syringing the 

 infested shoots with a strong decoction of 

 tobacco, tobacco liquor, wetting and dusting 

 with Scotch snuff, are amongst the prevailing 

 remedies. Fumigating with tobacco, where the 

 trees can be covered so as to retain the smoke, 

 is also destructive to the aphis' in every state 

 but in that of the egg, and dusting the trees 

 with finely-pulverised caustic lime is also effi- 

 cacious. Trees that have been painted over 

 during winter with spirits of tar, have been 

 found exempt from the attacks of aphides for 

 several years after. The following mixture, ap- 

 plied every year, or every other year, has been 

 found efficacious in the case of fruit trees gene- 

 rally, — viz. 1 lb. quicklime, 1 lb. Scotch snuff, 

 1 lb. sulphur vivum, 4 lb. lamp-black, 1 lb. soft 

 soap, mixed together in water until the whole 

 form into the consistency of thick paint, applied 

 by a painter's brush to the branches in February, 

 taking care that every part of the tree is covered 

 with the mixture. In preparing tobacco-water 

 for this and similar purposes, J lb. of strong 

 tobacco, steeped in 1 gallon of soft water for six 

 or eight days, occasionally stirring it, and squeez- 

 ing the tobacco to disengage the juice, will make 

 a liquid sufficiently strong for the purpose of 

 washing the shoots ; and if reduced by adding 

 another gallon of water, will be in a fit state for 

 syringing over the trees. 



The wood leopard-moth (Zeuzera asculi), fig. 

 199, is in its habits similar to the goat-moth, 

 fig. 198, living in the trunks of various trees, 

 the apple and pear amongst others. The cater- 

 pillar of this moth is 1 4 inches long, of a yel- 

 lowish colour, with four black spots on each 

 side of the segments, with the exception of the 

 thoracic and apical ones. The head is marked 

 with two black spots, and its feet consist of two 

 anal, six pectoral, and eight abdominal ones. 

 The males are hatched about the end of June, 

 and are much smaller than the female, which 

 measures about 2| inches when the wings are 

 expanded. The male is white, with semi-trans- 

 parent wings. The nervures are ochreous, with 

 many large black spots, having a green tint on 

 the superior, much smaller and paler in the 



3o 



