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JOUKNAL OF HOBTICULTURE AND COTTAGfi GARDENER. 



[ December 7, 1871. 



damp ashes, and more still on having close-fitting furnace ' 

 and ashpit doors— the ashpit door being especially fclose- 

 iitting. However high jour chimney, there will be no such 

 tearing draught, if no direct air, or the least possible amount, 

 reach the fuel through the grate bars. One precaution more. 

 In making up your fire for the last time under such circum- 

 stances, do not stir up or put the poker through the fire, rather 

 take the shovel and beat down the fire to the bars — this will 

 lessen the air passing — then put on what you want, and 

 cover over with ashes. Listly, do not suppose that you want 

 a constant fire in a fiue in a greenhouse unless the frost is 

 keen and continuous. For several nights in winter, with 

 merely a little frost, if the flue is properly heated, little more 

 heat will be required, as the flue will retain its heat a long time. 

 We think that by acting on these hints you will manage the 

 house at less expense, and we should be obliged if you will let 

 us know how you get on, and what plan was the most success- 

 ful. We say, Try the close ashpit door after the flue is becoming 

 hot, and do not seek to keep a constant fire. — Edb.] 



SOME PREDATORY INSECTS OF OUR 

 rjARDENS.— No. 23. 

 The proverb that the most insignificant foes are sometimes 

 most to be dreaded is rather hackneyed, yet it is true. The 

 gardener meets with a constant proof of it in the injury and 

 annoyance which the hosts of aphides, alias smotherflies, alias 

 plant lice, alias blight — the last name being certainly the most 

 vague — inflict upon him. There are many other species of 

 insects whose ravages are a great deal more observable; there 

 are some species which at times work much more mischief 

 than the aphides ever do, but the latter are an ever-recurring 

 pest, sparing few plants either in the kitchen or flower garden, 

 frequent in their visits to conservatories, and from their small 

 size and the tenacity with which they adhere to their various 

 food-plante, and their ingenuity at concealing themselves, 

 are not easily hunted out and destroyed. Has any poet ever 

 sung the praises or dispraises of the aphia tribe ? I find one 

 notice regarding them in the "Insect-Hunters," couched in 

 the peculiar Hiawathan metre in which that entomological 

 poem is composed : — 



" The noisome plant lice — 

 Smo'.herflies the farmers call them — 

 Smothering all the growth of summer, 

 Crowd mg till the shoots are hidden. 

 Leaves and buds concealed by numbers. 

 Anchored by their beaks sap-sucking. 

 Winged and wingless all together. 

 Their antennse long and wavering. 

 Gradual taper to the summit. 

 All their wings are quite transparent 

 When they have them, and not folded ; 

 All their feet are but two-jointed. 

 And their legs not formed for leaping." 



Does some critic remark that this is but lame verse? Let it 

 be remembered that it is written for beginners in entomology, 

 and the description has at least this merit, which cannot be 

 claimed for some very melodious poetical performances, that it 

 is according to nature and fact. But it may be queried, What 

 special end is subserved by these tiny insect hosts ? They act 

 not as scavengers, nor have they any particular beauty in their 

 appearance, nor do they, like some species of coccus, yield any 

 product important to man. (It is just possible, however, that 

 aphides do some good after all, in the way of removing plants 

 which are already diseased by accelerating their decay. They 

 swarmed upon the Potato plants which were affected by the 

 murrain, and hence were unjustly accused by some persons of 

 being a cause, if not the principal, while they were only an 

 effect). One of our most excellent of Scotch gardeners gives 

 it as his opinion that Providence sends aphides to make gar- 

 deners more watchful, and also more patient, than they would 

 otherwise be. Yet for all that he has no partiality for them, 

 and has often declared to me that he greatly prefers honest 

 caterpillars, which feed openly upon plant?, to such sneaking 

 fellows as aphides generally seem to be. Bat one of his puzzles 

 is this, that he cannot find any allusion in Scripture o sot 

 memorable an insect plague as the plant louse. His son, who 

 attends evening classes, and is keeping himself up to the 

 latest movements in science, has suggested to his parent that 

 probably these insects did not occur in eastern climes at the 

 time the Bible was written, the temperature not being con- 

 genial to them, but I don't think the old man received this 

 solution with any favour. 



But cannot aphides be turned to some aocount, for, thongh 



small, they are plentiful enough ? My slight acquaintance 

 with Sharpe Schemer, Esq., of this city, enables me to state 

 that he was engaged some lime ago in a series of experiments, 

 with a view to the extraction of some peculiar dye from their 

 carcases. He dropped this, however, and from his observa- 

 tions upon honeydew, and the relations existing between the 

 ants and aphides, having come to the conclusion that aphides 

 convert the juices of plants into sugar, he has now engaged in 

 the promotion of a company, the " Aphis Sugar Company," 

 capital £100,000, in 10,000 shares of .£10 each, hall to be paid 

 on allotment, and the remainder when the first specimens of 

 aphis sugar enter the market. Further particulars can be ob- 

 tained at the temporary — very temporary — cffices of the Com- 

 pany. As Mr. Schemer, however, was heard to remark the 

 other day, that as soon as he had received all that seemed 

 likely to be paid down on allotment he contemplated a journey 

 to America, it is most likely that the second payment will not 

 be called for in a hurry. 



Two very troublesome species of the aphis genus are those 

 known as A. Eafa; and Brassicas. The former of these also 

 bears the name of vulgaris, and is also, I believe, the vastator 

 of some authors. A few entomologists doubt the distinctness 

 of these two species, but I think it is unquestionable, though 

 both may be found occasionally haunting the same plants. 

 Some of the differences may be thus stated. In A. Eapas, it 

 it be examined by a hand-magnifier, it will be seen that the 

 collar is brown, the abdominal tubes long ; the iridescent wings 

 have lightish brown nervures. A. Brassicie has a black collar, 

 the tubes are much shorter, and the wings, also iridescent, have 

 stouter nervures, which are of a brownish black. The females 

 of Brassica: are also slightly mealy, the abdomen seeming 

 larger than in Bapje. The economy of both is very similar. 

 Unlike many other aphides, they are most active towards the 

 end of the summer. A. Ea[» is rarely noticed much before 

 midsummer, and though we can hardly suppose that the first 

 brood hatched from the eggs laid in the autumn is only then 

 appearing, it is evident that their multiplication goes on but 

 slowly for a certain time. I have not myself observed any 

 males of the species in the spring or summer, and suspect that 

 in both this and Brassicse there is a succession of female 

 broods until towards autumn, when the winged males appear. 

 The "lords of the creation" in the domain of aphis life are 

 not in request until the succession of broods has nearly 

 reached its close. Brood alter brood appears without the in- 

 tervention of males, the wing'ess females producing Iheir 

 young alive, and these, if the weather is favourable, increase 

 rapidly in size, and are soon able to be themselves parents. 

 Prom September, on unlil nearly the end of November, we find 

 A. Brassicie abroad with a commingling, then, of all sizes, 

 winged and wingless, feeding amicably together, and sheltering 

 in the curled leaves of Cabbage and Broccoli plants when the 

 weather is cold. The different species of aphis apparently 

 stand cold better than do most other insects. Dry weather is 

 much in their favour, there is no doubt. 



Many years ago Mr. Curtis noted the fact that A. Brassicas 

 was partial to Swedish Turnips. Messrs. Hardy and Langland 

 report that in 1870 it did much iijuiy to these in the Border 

 counties, confirming Mr. Curtis's observation. Only a few 

 stragglers were seen at first, but they increased rapidly just as 

 the plants were throwing off their outer leaves. The dry 

 weather and mildew then kept back the young leaves, and as 

 they slowly developed they were drained of their sap by the 

 aphides, which now seemed to defy all attempts made to di- 

 minish their numbers. One man, indeed, tried the experiment 

 of cutting off the tops and dealing them away ; the plants 

 sprouted again, and were none the worse, but others did not 

 like to venture on so unusual an expedient. The later sowings 

 suffered very little. At the same time that Aphis Brassicfe 

 was infecting the Swedes, the white and yellow Turnips were 

 furnishing food to crowds of Aphis Eapa). A migration of the 

 Turnip aphides was noticed by Mr. Hardy ; this occurred at 

 the end of September. Concerning this he says, " For more 

 than a week during the calm and genial weather they rose in 

 succession from Turnip fields along the valleys until they were 

 almost incorporated with the air, so intensely crowded did 

 they become. At night, or during dull days, they stuck to the 

 threshold, to the grass by wall sides, or gathered upon hedges 

 or trees. Many fell into the waters, or were swept from the 

 grass on the brink. At length came some heavy showers of 

 rain and hail, which cleared the air, and the insects mostly 

 perished." 

 On the question as to the cause and extent of the migrations 



