256 



JOUBNAL OF HOETICULTUEE AND COTTAGE GAEDENEE. 



t AprU 6, 1871. 



of rich soil in October or November, with glass sashes over 

 them. This rich Violet does better in a cold pit than in a 

 window, though of all Violets it stands a little forcing best. 



If some of onr readers can further help onr Geraninm 

 Cottage correspondents we shall feel obliged, and the more 

 especially as we know but little of the new Violets, though as 

 anxious to know about them as if we were not confirmed " old 

 Gooseberries."] 



SOME PKEDATORY INSECTS OF OUR 

 GAEDENS.— No. (i. 



Gakdeneks, like anglers, ought, I think, to be meditative 

 men. In their occupation there is nothing that need put 

 them in a hurry, and many departments of horticulture give 

 abundant opportunities for thought ; yet it would not do for 

 them to be pondering too frequently over their insect enemies, 

 seen and unseen. How the gardener thinks about the latter 

 will depend very much upon his natural temperament. He 

 may, if of a genial disposition, congratulate himself that it is 

 a very good thing some of those insects that are most trouble- 

 some in the garden are not visible, and are chiefly known by 

 their results, because, as they could not be effectively reached 

 and operated upon, it is just as well not to know annoyances 

 which cannot be remedied nor effectually checked. But if he 

 be of a pensive cast of mind he may ruminate over insect pests 

 imtil the seen eiJects of their jaws seem as nothing compara- 

 tively to the ravages which may be going on through the 

 agency of insidious enemies lurking in the twig, or within the 

 curled-up leaf, or burrowing in the ground to'devonr the root and 

 bulb, or emerging therefrom at night to work, side by side, 

 with snails and the like upon the young leaves and the buds. 

 Nay, carrying the reflection a little further, he may drop a tear 

 amongst his early Lettuces as he considers that this is very 

 nearly the same tlaing that occurs in human life, where a man's 

 worst enemies are so often found not to be those who openly 

 oppose him, but those who as neutrals or as seeming friends win 

 his trust, or at least do not awaken his suspicion. But let me 

 not moralise any farther. I should not, perhaps, have fallen 

 into this strain had not my attention been called this very day 

 to a tolerably well-known garden enemy, which we really 

 cannot somehow be angry with in spite of the harm it has 

 done us. 



Making a " tour round my garden " I observe just now that 

 sundry branches and twigs on my Carrant bushes give evident 

 marks of the destructive influence put forth by the caterpillar 

 of the Currant Clearwing (Sesia Tipuliformis). It is only now 

 and then that this 

 caterpillar will ac- 

 tually kill a bush, 

 though I have 

 noticed some die 

 which have had re- 

 peated attacks made 

 upon them through 

 a series of years. 

 The effect to be 

 generally noted is 

 the dying-oft of 

 certain branches, 

 the rest of the bush 

 flourishing, and ap- 

 parently not having 



Sesia Tipulijormis. 



its fruit-bearing powers at all interfered with by the insect ; for, 

 indeed, were the boughs mined by the caterpillar to die off at 

 once, it would be unfavourable to the continued existence of 

 the species, since its nutriment is only the living pith. Nor, 

 BO far as my own observations go, do the shoots in which it 

 has penetrated die the year in which they have suffered ; I 

 believe that they manage to put forth leaves the next season, 

 and perhaps another. The Black Currant, it is notorious, 

 suffers more from the attacks of this Clearwing than do the 

 Ked and White Currants. I have some suspicions that it may 

 occasionally be found mining in the canes of the Easpberry, as 

 the moths not unfrequently settle on Easpberry bushes. When 

 it has once gained a footing in a garden this species is not 

 easily eradicated. In Chelsea it has been well known for many 

 years, and some of the earliest recognised British specimens 

 were taken there. I have seen signs of its presence, however, 

 in vaiious market gardens about London, iilany localities 

 have bean named throughout England and Sootland ; whether 

 it occurs in Ireland I cannot say. 



I used to imagine that the eggs were deposited by the females 

 on the terminal twigs, but recent observations do not confirm 

 this, the mines of the young caterpillars being seen in a 

 variety of positions, and at all ages they maybe found working 

 both upwards and downwards in the shoots and boughs, it being 

 noticeable that tbey prefer the latter as they increase in cize. 

 At the commencement of the winter the caterpillars are small ; 

 they continue, however, to feed throughout the cold season 

 with little or no intermission. Under certain circumstances 

 they will mine down a twig or branch which has been tenanted 

 before by a more juvenile individual, or by an individual of the 

 preceding year ; this is, however, unusual. Some tracks will 

 be found in which a caterpillar has worked along for a time, and 

 then turned and retraced its course. The external air these 

 caterpillars have a decided objection to, nor do they ever 

 emerge in order to migrate from one bush to another, as is said 

 to be the cise with some internal feeders. 



Ordinarily, the caterpillar of the Currant Clearwing is pre- 

 pared to become a chrysalis by the end of April ; I have seen 

 seasons when the change has been much later, through growth 

 having been retarded by a chilly spring, but even then the moth 

 was not at the usual time. This year I find the species is 

 pretty forward, considering the length of the winter, though 

 there are some differences of size amongst those I have turned 

 out of " house and home." Not a particularly pleasant-looking 

 caterpillar, certainly, white and flabby, yet of a form adapted 

 to its tunnelling life. 



The chrysalis is most usually placed at some node, and a 

 portion of the wood is removed by the caterpillar ere it changes, 

 only such a film being left as the chrysalis can force its way 

 through, the segments being furnished with hooks ; and through 

 the hole it makes when the moth is ready to emerge the empty 

 case is left as a relic, and an intimation to the gardener that 

 the particular individual has done his work and taken himself 

 off to enjoy the June sunshine. The moth, indeed, is not at 

 all moth-like, the transparent wings and slim body, coupled 

 with the circumstance that it delights to fly in bright weather, 

 would lead many to suppose it some species of fly, and at the 

 same time it so happens there are several species of Diptera 

 on the wing rather resembling it in appearance. Though fond 

 of sunshine, this insect takes short flights, and it is notable 

 during their season how soon a passing cloud will make all the 

 moths settle down on the Carrant leaves. Occasionally in the 

 evening specimens will come to flowers, but this is not a fre- 

 quent occarrence. Earely do they fly far from the bushes in 

 which they have been bred. A singular account appeared in 

 one of our entomological journals some years ago, stating that 

 a number of these moths had been taken in a kitchen. The 

 only explanation in this case, if the name was correctly applied, 

 must be this, that somewhere adjacent to the place indicated 

 chippings of Currant bushes had been put, and from these, 

 which had contained pupje of the species, moths emerged at 

 the usual time. The only way to check the ravages of this 

 Clearwing is to capture as many of the moths as possible, and 

 the sooner after their appearance the better, ere the females 

 have had time to deposit eggs. 



There is another species of Clearwing not at all infrequent 

 in some of our London suburbs, and which is pretty generally 

 distributed in the south of England. This is the Eed-belted 

 Clearwing (Sesia Myopasformis), and as it appears in the winged 

 state at or about the same date as the preceding, they may be 

 sometimes seen sporting together in our gardens. This species 

 has a red belt, which at once separates it from the Currant 

 Clearwing with its yellow bands. Another red-belted species is 

 known, however, a feeder on Birch wood, occurring in different 

 spots from Myopa?formis, and being a larger species. I should 

 hardly have supposed that the species before us could have 

 done material injnry, but a market gardener assures mo that 

 in his orchards to the south of Loudon in certain seasons these 

 moths are numerous enough to affect the frnit-bearing powers 

 of some of the Pear and Apple trees there. That they actually 

 kill trees, or even saplings, I do not believe ; the latter do not 

 seem to be usually objects of the attack. The caterpillar, 

 like that of Sesia Tipuliformis, lives from autumn to spring, 

 and feeds with little or no intermission. When occurring on 

 Pear trees it is found most frequently in the wood of the trunk. 

 Newman states that he has seen " between sixty and seventy 

 in a piece of Pear-tree wood about 3 inches lone," so that they 

 must be pretty closely packed sometimes. Feeding on the 

 Apple, it prefers the branches. I do not see that any effectual 

 means could be devised for destroying the caterpillar of this 

 species, and the moth is not so easily netted as its relative. 



