468 



HARDY FRUIT GARDEN. 



subsisted upon. They remain two years and up- 

 wards in their larva state, and during that period 

 cast their skin eight times. Pupation usually 

 takes place in spring, and shortly before that the 

 caterpillar becomes of a light ochre-yellow colour. 

 The abdomen of the pupa is yellow. The back is 

 furnished with strong spines, sometimes black, 

 and at other times of a reddish-brown colour. 

 The cocoon is constructed of chips of wood, 

 gnawed off and cemented together with a glu- 

 tinous secretion, and lined with silk. It is placed 

 immediately within the opening of the tree, 

 which enables the pupa to press itself partially 

 out of the hole when it arrives at that state of 

 maturity at which the shell bursts, and when 

 the moth is in a state to emerge into the air, 

 which is usually in June and July. The female 

 is furnished with a strong ovipositor, by means 

 of which she introduces her eggs into the bark 

 of the tree, the caterpillars, while young, living 

 between the outer and inner bark, and as they 

 get older and stronger they penetrate into the 

 solid wood. The means most likely to keep this 

 formidable insect in check are to endeavour to 

 capture the moth during night, either by catch- 

 ing it while on the wing in a gauze net, or by 

 decoying it to its destruction by placing burning 

 lights near to where it abounds ; fumigating it 

 while in the caterpillar state within the tree, by 

 blowing fumes of sulphur or tobacco into the 

 holes ; or mechanically, by thrusting iron wires 

 into the holes, or immuring them within their 

 wooden prison by stopping up the holes in such 

 a way as to prevent their escaping, or the en- 

 trance of the limited amount of air necessary 

 for their existence. 



The pear saw-fly, Tenthredo hcemorrhoidalis 

 of Fabricius, attacks the fruit of the pear, within 

 which she deposits her eggs. The fly appears 

 towards the latter end of May and beginning 

 of June. The female chooses the under side of 

 the leaves of the pear tree, where she lays her 

 eggs to the number of from forty to sixty. 

 The eggs are merely attached to the leaf, 

 and are arranged with extraordinary precision, 

 one row being quite regular, and the next 

 so placed that the eggs in it cover the spaces 

 between those in the row immediately in front 

 of it. In form they are longish, in colour yel- 

 lowish, and have the appearance as if besmeared 

 with mucous matter. In a few days the young 

 caterpillars are hatched, and are at first of a 

 whitish yellow, changing gradually to a darker 

 colour. Kollar describes the caterpillar as be- 

 ing hatched within a few days after the eggs are 

 laid, and "as soon as it is exposed to the light, 

 it spins a web over itself, the threads of which 

 proceed from its mouth. The caterpillar never 

 appears out of this web, and when it has partly 

 eaten a leaf, it spins itself a web on another, and 

 always in company with other caterpillars. It 

 has a black head, and immediately under the 

 throat two black dots. The other parts of the 

 body are ochre coloured and transparent, with- 

 out hairs. It measures from 9 to 10 lines long. 

 The two fore feet, and the two upon the last 

 segment, are finely tapered, so that they rather 

 resemble claws than feet, because they do not 

 use them for crawling, but to draw themselves 



out of and into their webs. These caterpillars 

 attain their full size in five weeks ; they then 

 leave the trees, and bury themselves deep in the 

 ground." Here again we have a remedy pre- 

 sented to us, by destroying the caterpillar in the 

 soil, as has already been suggested. But man 

 has here also excellent assistants in keeping in 

 check this destructive insect. The caterpillar 

 or larva of Ophion mercator, an ichneumon fly, 

 lays its eggs in the body of the pear saw-fly, 

 just as the latter has attained its full size, and 

 just before it drops from the tree to the ground, 

 living upon its vitals, and making use of its 

 empty skin for a winter shelter. 



The pear chermes, (Chermes pyri Schmidber- 

 ger, Psylla pyri Stephens.) The chermes is al- 

 lied to the aphis, and, like them, extremely 

 destructive to such fruit trees as each species 

 prefers. The chermes of the pear infests the 

 young shoots mainly, and by insinuating its 

 long and delicately-formed tongue into the ten- 

 der bark, it not only sucks up the juices, but 

 defiles the leaves and shoots with its disagree- 

 able and abundant excrement. When full- 

 grown, this insect is somewhat larger than a 

 large aphis, having a broad head, terminating 

 in front in two cone-like protuberances. The 

 mouth, instead of being situated in the head, is 

 placed in the middle of the breast, behind the 

 hind and fore feet. The male is somewhat of a 

 crimson colour, shaded with dark brown or 

 black. The female is without shading, and is 

 entirely crimson. The wings in both sexes are 

 pure white. They make their appearance in 

 spring in their winged state, and immediately 

 pair, after which the female lays her eggs in 

 great numbers on the young leaves and blos- 

 soms, as well as on the young shoots and embryo 

 fruit. Hatching is completed in a few days, 

 the young chermes resembling plant-lice, but 

 being of a dark yellow colour, and" furnished 

 with six feet. Kollar remarks, " They are called 

 nymphs or larvae in this state, according to the 

 extent of their development. After a few days 

 they change their skins, and become darker, and 

 somewhat reddish on the breast. After changing 

 their skins, they quit the leaves, blossoms, and 

 fruit, and proceed more downwards to the bear- 

 ing wood and the shoots of last year, on which 

 they fix themselves securely one after the other 

 in rows, and remain there till their last trans- 

 formation. When the nymphs have moulted 

 for the last time, and have attained their full 

 size, the body swells out by degrees, and be- 

 comes cylindrical. They then leave their as- 

 sociates; and before they lay aside their nymph- 

 like covering, they search out a leaf, to which 

 they fasten themselves firmly, and appear as if 

 they were lifeless. After a few minutes, the 

 skin splits on the upper part of the covering, 

 and the winged insect proceeds from it." Dur- 

 ing summer it flies about, and towards autumn 

 selects a place of shelter, and remains there till 

 early in spring, when it again begins its work of 

 regeneration. The natural enemy to this chermes 

 is the ant, which is attracted to the twigs 

 infested by the copious fluid-like excrement 

 emitted by the chermes, which they devour as 

 well as many of the insects that produce it. ThQ 



