112 



THE GAKDENER'S ASSISTANT. 



on the back. The moths may be found from 

 June till August. 



Remedies. — The habits of the caterpillars, 

 pupae, and moths are similar to those of the 

 Dart Moths and Pot-herb Moth, so that the 

 same remedies will apply here. 



Stem Borers. 



Apple Clear-wing Moth (Trochilium myo- 

 pceforme). — When flying, this moth measures 

 only 8 to 10 lines across the transparent wings, 

 the front pair of which have dark margins and 

 a central spot. The hind-wings have blackish 

 fringes. The body is black, with a red ring on 

 the abdomen. The grub is about § inch long, 

 white or pale-brown, from being covered with a 

 dark fluid, thinly hairy, with a shining pale- 

 brown head, and 16 legs, of which the 6 true 

 ones are pale-brown. It feeds beneath the bark 

 of the Apple, in company with the "Wceberian 

 Tortrix, during autumn and winter, also in the 

 stems and branches, and the perfect moth comes 

 forth in June and July. The pupa lays up in 

 the stem. 



Remedies. — Badly - infested trees present a 

 sickly and diseased appearance, and the bark 

 becomes broken, rough, and dies in places. 

 Such trees have too long been neglected, and 

 being quite useless, should be rooted up and 

 burnt before the end of April, so as to destroy 

 the grubs and pupa?. Other remedies given for 

 theWoeberian Tortrix (seeunderBARK Enemies) 

 will also apply here, and any dressing to the 

 bark should be applied in the beginning of June, 

 and again in July, while the moths are on the 

 win- 

 Carnation Maggot (Hylemyia nigrescens). — 

 The perfect insect is a dark-brown or black, 

 hairy, two-winged fly, similar, and related to 

 the species which gnaws the roots of Cabbages, 

 and that which bores into the bulbs of Onions. 

 The maggot is cylindrical, tapering to the head, 

 cut short at the tail, round the edge of which 

 are blunt tooth-like processes, with two little 

 knobs tipped with brown on the flattened end; 

 it is also legless, pale-yellow, wrinkled at the 

 sides, and furnished with a horny, black, forked 

 and hooked process serving as jaws, with which 

 it tears its way down the centre of the shoots 

 and stems of Carnations and Pinks, such as Her 

 Majesty. Layers and seedlings in the open 

 border suffer more than indoor plants, and the 

 evil is continued in cold frames if the lavers 

 are potted up. The eggs are very often laid 

 apparently on the unexpanded leaves forming 



the long central bud of the shoots, for the 

 newly-hatched grub eats through several of them 

 at this stage in trying to penetrate the pith of 

 the shoot; after this it frequently ascends the 

 leaves from 1 to 3 inches in quest of rich food, 

 going down again as the leaves shrivel from the 

 injury. Some cultivators believe that the grub 

 pierces the leaves and goes down them. 



Remedies. — Syringing occasionally with soap- 

 suds and tobacco-water from the beginning of 

 August to the end of September might serve 

 to render the plants distasteful to the fly, and 

 prevent the laying of eggs upon them. The 

 presence of the maggot should be looked fcr 

 before it gets into the shoot if possible, and the 

 affected leaves removed and burnt. If already 

 in the shoot, the crown leaves will readily come 

 away when lightly pulled. The only remedy 

 then is to cut away joint after joint, till solid 

 pith is reached, or the maggot can be pulled out 

 with a pin. It is hopeless to expect the plant 

 to recover, or to check the mischief until the 

 enemy is secured, unless it has passed into the 

 pupa stage. No careful cultivator should delay 

 the remedy till this happens. Shoots already 

 ruined must be burnt, to destroy any maggots 

 that may be in them. 



Cattleya Fly. — See description and reme- 

 dies under Boot Enemies. 



Celery-stem Fly {Piophila Apii). — This in- 

 sect is as large as the Celery Fly, black, shiny, 

 and thinly clothed with golden -gray hairs. 

 Greater part of the head is chestnut, the veins 

 of the wings yellow, and the legs straw-coloured. 

 The maggot is yellowish-white, and similar in 

 structure to the Carnation Maggot. It pene- 

 trates the solid root-stock, or stem, of Celery, 

 working its way up into the leaf-stalks, making 

 burrows, the lacerated surface of which becomes 

 rusty-red, thus destroying the appearance and 

 value of the blanched product. This work of 

 deterioration goes on during winter, especially 

 in mild weather, and in early spring, till the 

 maggot pupates, and the fly comes forth in 

 May. 



Remedies. — As in the case of the Carnation 

 Maggot, it is useless to apply insecticides. The 

 only real remedies rest with gardeners and 

 growers, who should carefully collect and burn, 

 or otherwise effectually destroy, all heads or 

 sticks of Celery seen to be infested with the 

 grub when dug up. It may generally be cal- 

 culated that the grubs are still in the leaf-stalks 

 or stems up to the end of February, so that no 

 infested rubbish should be thrown away nor 

 placed on the refuse-heap, because the grubs 



