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JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 



t September 7, 1876. 



prising rapidity in the summer season, utterly contemning the 

 absence of the masculines of the race, a small array of which 

 appear towards the end of autumn. Without theBe, however, 

 it is assumed the deposition of eggs would not occur, and it is 

 in the egg state that the bulk of the aphis families pass through 

 the dreary season, though a few rather tough long-lived in- 

 dividuals struggle on from autumn to spring in sheltered 

 spots if the gardeners will leave them alone. Well, not to be 

 prolix, had we been asked to arrange the details of entomo- 

 logical life, it is possible we should have decided that aphides 

 had better not be quite so prolifio, and we might have trans- 

 ferred this capacity of breeding to some species that are beau- 

 tiful and not injurious. But we may as well reconcile our 

 minds to matters as they are, and perhaps after all there is 

 some sense in the consolation offered by one naturalist, who 

 asserts that many of these seeming pests serve to indicate 

 plants that are weakly, or which require looking after. It 

 may be allowable here to put emphaBis on a remark which is 

 not original, that in destroying aphides a random proceeding 

 may even be productive of more harm than good. I will not 

 say anything against syringing and fumigating, though these 

 kill frequently both the aphides and the parasites that prey 

 upon them ; but I will give an instance in the case of hand- 

 picking. In a Hop plantation this summer, on some of the 

 lower leaves of the bine there were numerous aphides, and 

 thickly interspersed among these the eggs of one or more 

 species of Coecinella. To have removed the leaves indiscrimi- 

 nately and burned them, as many persons would have done in 

 such a case if they did anything, would have been to destroy 

 friends with foes, and it was thought better even at some out- 

 lay of labour, to go from leaf to leaf crushing the aphides 

 but leaving uninjured the eggs of their devourers. 



Now, the aphides which appear so numerously both on cul- 

 tivated and uncultivated plants , scarcely a species being entirely 

 free from these pests, may be at once separated, if not on 

 strictly scientific principles yet very naturally, into two great 

 divisions. To the first belong the aphides that feed exposed 

 or only concealed by the bodies of their relatives (for it is 

 observable that there is sometimes a double layer of these 

 insects) ; to the second belong those that are partly or entirely 

 hidden from view, either by their own exudations or by their 

 habit of contorting the leaves and stems of plants, of burrow- 

 ing in their roots, or in some way causing an unnatural growth. 

 These mischief-workers in secret are most annoying to the 

 gardener, for they necessarily escape various bird and insect 

 enemies. Rain does not materially affect them, and their 

 ravageB are often unobserved until it is too late. It is amus- 

 ing to notice., however, the diligent manner in which the ants 

 will hunt-up the hidden aphides, often thereby intimating to 

 the observer the fact of the presence of these destroyers of 

 plant vitality. It has been suggested, though it is hardly 

 capable of proof, that the aphides which by their operations so 

 greatly disfigure some plants and shrubs, or even trees, must in 

 some way poison or injuriously affect the species they frequent, 

 otherwise the results would not be as we find them. Among 

 the gall-producing insects of the Hymenopterous order, it is 

 certain there are some that by their punctures set np an un- 

 healthy action, ending in morbid growths. But with the 

 aphides it is more likely that all the evil they do arises from 

 the exhaustion they cause by their rapid suction of the sap ; 

 perhaps the immense number of small punctures a party of 

 them make may cause a sort of irritative action, leading to the 

 odd twists and contortions of aphis-haunted shoots. The most 

 singular locality for aphides, to my thinking, is within the 

 roots of plants, where swarms of them are now and then dis- 

 covered. Possibly they may be more plentiful iu these situ- 

 ations than we should imagine were they always identified, but 

 few persons would expect to discover aphides in roots : hence, 

 from their small size, they are overlooked. We might ask 

 several questions about these not easily answered, and wonder 

 if they have winged representatives, or if they perform migra- 

 tions like the rest of the brethren, or if they first became 

 feeders upon roots, because their ancestors were carried under 

 ground and kept prisoners in ant hills, for it is the habit of 

 ants, as is well known, tomake captives of their aphis favourites, 

 their " milch kine," as the aphides have been facetiously called. 

 Though it is almost as odd that aphides should cluster in the 

 interior of an Apple as in a root or bulb, for Mr. Newman re- 

 cords the discovery of that fact as far baok as 1835. " I have," 

 he says, " cut open Codlin after Codlin and found the pips 

 garrisoned with them ; not one lone aphis, but a whole troop 

 of all sizes. When I let in the daylight there was a consider- 



able sprawling and waving of legs, and no small alarm in the 

 hive, but by degrees they got used to light and fresh air, and 

 were quite still. I tried to tickle them with a straw in order 

 again to watch their movements, when, lo and behold, they 

 were all dead — gathered to their fathers ; gone to the tomb oJ 

 all the Capulets ! Some had heaved anchor and dropped from 

 the pip; others, fixed more firmly, had died at their posts, 

 and, tucking their legs together under them, hung by their 

 beaka." 'Twas an extraordinary circumstance that they should 

 die on contact with the air, indicating clearly that they could 

 never have worked their way from the outer world into the 

 Apple ; and as the point has not been made out by research 

 we can only construct a theory on it, assuming that the eggs 

 must be deposited outside the Apple while it is yet juvenile, 

 and that the young aphides burrow in. This would show a 

 different habit to tkat prevalent amongst the majority, where, 

 aB I have noted, eggs are only laid in the winter. 



If we " collar " the first aphis we catch upon our coat-sleeve, 

 or pick off one off our Geraniums, and subject it to a slight 

 examination (should it be a tolerably plump one we shall not 

 require a magnifier to help us), we perceive that the oval body 

 is supported by six slender legs, and at the extremity of the 

 body project two short knobs, which are tube-like. The insect 

 tucks its head under, so that we do not readily see the pro- 

 boscis or sucking apparatus, though the long antennas which 

 adorn the head are visible enough, and occasionally the eyes 

 shine out when the general colour is pale. Should the aphis 

 be in the winged state the difference in size between the fore 

 wings and the hind wings is very perceptible ; they are also 

 held perpendicularly, not sloping over, as in the Psyllidse. 

 Ordinarily the motion of a crawling aphis is but tardy, though 

 some species display more activity than others. As to colour 

 — well, there is a great variety in this respect, and even in the 

 same species the hue differs with the age and sex. Thus in 

 the excessively common Aphis Tilise the female is pale yellow, 

 the male yellow and black spotted. In the species which 

 abounds on the common Elder the winged individuals are 

 much darker than the wingless, although the latter may beat 

 them in size on exact measurement. On the Elder, as also on 

 neglected Roses and other plants, aphides will be so numerous 

 at times as to form a double layer, and one naturalist ingeni- 

 ously explains the reason of this, telling us that the upper 

 layer is engaged in the continuance of the species, and that 

 the lower layer is busy feeding. This is more clever than true, 

 for on this idea of the arrangement all the old folks must be 

 above and the young folks below if we suppose that those once 

 above eat no more but die off after they have become parents. 

 But so far as I have noticed, aphides large and small are 

 commingled in both these layers, therefore I imagine that they 

 shift about somehow and take turns at getting sips of the sap. 

 And in this place it may be well just to advert to the question 

 as to the early nourishment of the young aphides, since, on 

 the one hand, it has been positively asserted that they draw 

 their food at first from the maternal tubes, and, on the other, 

 that this sweet secretion (called also by the name of honeydew) 

 is only directly taken from the bodies of aphides by their 

 faithful attendants the ants. If we were to accept the former 

 statement, then, of course, a female aphis which has proved a 

 parent of a goodly array of young ought to have them swarm- 

 ing about her just as the reader must have seen a broad-sided 

 sow attended upon by her litter of pigs. This does not seem 

 to be the case ; the recently hatched aphides take their places 

 orderly enough, but not in such positions towards their affec- 

 tionate (?) parent as would lead us to surmise she is also nurse. 

 Yet it may he that young aphides do occasionally devour the 

 honeydew, as this food is attainable so easily, and is, indeed, 

 only a very slight modification of the juices of the trees or 

 plant on which it occurs. But I believe aphides, however 

 juvenile they may be, are well able to shift for themselves and 

 draw from the vegetable world direct the food that Nature im- 

 pels them to seek. 



Proceeding next to give a brief outline of the annual circuit . 

 along which aphis life runs, I have to remark that though 

 several naturalists who were his predecessors in the study of 

 the habits of aphides had observed the presence of wingless 

 females in great numbers, either alone or in company with 

 the winged, Charles Bonnet, who published his discoveries in 

 1745, was the first to see and record the astonishing fact that 

 successive generations of aphides appear through the summer, 

 all of which are females. He purBued the rearing of the in- 

 sects in confinement for five generations, and other ento- 

 mologists have found that brood after brood, under certain 



