404 



BUGS, INSECTS, ETC.— REMEDIES FOR. 



as, considering their size, they are great 

 travelers, and show a strong predisposi- 

 tion to drop, their natural lightness, as in 

 the case of the young Cicada, and of other 

 insects which hatch above, but live under 

 ground, enabling them thus to reach the 

 earth with ease and safety. At all events, 

 we know, from experiment, that the young 

 gallcecola, if confined to vines on which 

 they do not normally, and perhaps can 

 not, form galls, will, in the middle of sum- 

 mer, make themselves perfectly at home 

 on the roots. 



Type Radicicola, or Root-inhabiting. — 

 We have seen that, in all probability, gal- 

 lcecola exists only in the apterous, sha- 

 greened non-tubercled, fecund female 

 form. Radicicola, however, presents itself 

 in two principal forms. The newly- 

 hatched larvae of this type are undis- 

 tinguishable, in all essential characters, 

 from those hatched in the galls ; but in 

 due time they shed the smooth larval 

 skin, and acquire raised warts or tubercles 

 which at once distinguish them from gal- 

 Icecola. In the development from this 

 point the two forms are separable with 

 sufficient ease : one (a) of a more dingy 

 greenish yellow, with more swollen fore- 

 body, and more tapering abdomen; the 

 other, (b) of a brighter yellow, with the 

 lateral outline more perfectly oval, and 

 with the abdomen more truncated at tip. 



The first, or mother form, (Fig. 45, f, 

 g), is the analogue of galcecola, as it never 

 acquires wings, and is occupied, from 

 adolescence till death, with the laying of 

 eggs, which are less numerous and some- 

 what larger than those found in the galls. 

 We have counted in the spring as many as 

 two hundred and sixty-five eggs in a clus- 

 ter, and all evidently from one mother, 

 who was yet very plump and still occu- 

 pied in laying. As a rule, however, they 

 are less numerous. With pregnancy this 

 form becomes quite tumid and more or 

 less pyriform, and is content to remain 

 with scarcely any motion in the more se- 

 cluded parts of the roots, such as the 

 creases, sutures, and depressions which 

 the knots afford. The skin is distinctly 

 shagreened (Fig. 45, h) as in gallcecola. 

 The warts, though usually quite visible 

 with a good lens, are at other times more 

 or less obsolete, especially on the ab- 

 domen. The eyes, which were quite per- 

 fect in the larva, become more simple 



with each molt, until they consist, as in 

 gallcecola, of but triple eyelets (Fig. 45, k) r 

 and in the general structure this form be- 

 comes more degraded with maturity,, 

 wherein it shows the affinity of the species 

 to the Coccidm, the females of which, as 

 they mature, generally lose all trace of the 

 members they possessed when born. 



The second or more oval form (Fig. 

 45, e) is destined to become winged. Its 

 tubercles, when once acquired, are always 

 conspicuous; it is more active than the 

 latter, and its eyes increase rather than 

 diminish in complexity with age. From 

 the time it is one-third grown, the little 

 dusky wing-pads may be discovered,, 

 though less conspicuous than in the pupa 

 state, which is soon after assumed. The 

 pupae (Fig. 48, <?,/,) are still more active, 

 and, after feeding a short time, they make 

 their way to the light of day, crawl over 

 the ground and over the vines, and finally 

 shed their last skin and assume the winged 

 state. In this last molt the tubercled skin 

 splits on the back, and is soon worked off, 

 the body in the winged insect having 

 neither tubercles nor granulations. 



In the great majority of insects the 

 wings in the pupa are simply compressed 

 and thickened without being folded, and 

 in the imago they expand without mate- 

 rial change in form. Those of our Phyl- 

 loxera are rolled up both from the sides 

 and the end, and, in expanding, they un- 

 roll; the whole operation requiring but 

 about five minutes. At first, and for some 

 time after the molt, the color of the body 

 of the new-fledged Phylloxera is of a uni- 

 form bright, deep yellow, with the wings 

 white and rather opaque, and the eyes 

 brown. The dark thoracic band and 

 more diaphanous and smoky nature of 

 the wings are gradually acquired in the 

 course of a day, and the insect finally 

 presents the appearance of Fig. 48, g, h.. 

 The wings when highly magnified are 

 seen to be thickly covered with minute 

 hooks. 



These winged insects are most abund- 

 ant in August and September, but may 

 be found as early as the first of July, and 

 until the vines cease growing in the fall. 

 The majority of them are females, with 

 the abdomen large, and more or less 

 elongate. The veins of the front wing 

 are not connected, and, by virtue of the 

 large abdomen, the body appears some: 



