67 



Fig. 44. 



" Type Radioioola or Root-inhabiting. — We have seen that, in all probability, 

 gallcecola exists only in the apterous, shagreened, non-tubercled, fecund female from, liadici- 



cola, however, presents itself in two principal 

 forms. The newly-hatched larva) of this 

 type are undistinguishable, 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 gallce- 

 cola. In the development from this point 

 the two forms are separal)le 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. 44,/, </,) 



is the analogue of gallcecola, as it never ac- 



»s. „ . , m- I ■ I 1 . quires wings, and is occupied, from ado- 



T\-rs Radkmcola.— a. roots of Camton vine, sliowius; relation "l p ' .111' /■ 



of swellings to leaf-galls, and power of resisting decomposition ; leSCenCC till death, With the laying 01 eggS. 



Lne r^/.'^^.Trm^oTmore mXre ifei ^ii'^^Sfoi^'of &! which are Icss Dumerous and somewhat larger 



i, tubercle .-j, transverse folds at borders of joints ; k, simple eyes, thau thoSe found in the galls. I have COUntcd 



in the spring as many as two hundred and si.xty-five eggs in a cluster, and all evidently from 

 One mother, who was yet very plump and still occupied in laying. As a rule, however, they 

 are less numerous. With pregnancy this form becomes quite tumid and more or less pyri- 

 form, and is content to remain with scarcely any motion in the more .secluded parts of the 

 roots, such as the creases, sutures and depressions, which the knots afford. The skin is dis- 

 tinctly shagreened (Fig. 44, 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 abdomen. The eyes, 

 which were quite perfect in the farva, become more simple with each moult, until they consist, 

 as in gallmcola, of but triple eyelets (Fig. 44, k,) and, in the general structure, this form becomes 

 more degraded with maturity, wherein it shows the affinity of the species to the C'occidce, 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. 44, e,) is destined to become winged. Its tubercles 

 when once acquired, are always conspicuous ; it is more active than the other, 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 conspicuously than in the pupa state, 

 which is soon after assumed. The pupae (Fig- 4.'), e, /,) 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 their last moult the 

 tubercled skin splits on the back, and is soon worked oflF, the body in the winged insect having 

 neither tubercles nor granulations." 



" The winged insects are most abundant 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 From two to five eggs may 

 invariably be found in the abdomen of these, and are easily seen when the insect is held up 

 to the light, or mounted in balsam or glycerine." 



" As fall advances the winged individuals become more and more scarce, and as winter 

 .sets in only eggs, newly-hatched larvae, and a few apterous egg-bearing mothers, are seen. 

 These last die and disappear during the winter, which is mostly passed in the larva state, 

 with here and there a few eggs. The larva^ thus hibernating (Fig. 44. /*) become dingy, with 

 the body and limbs more shagreened and the claws less perfect than when first hatched ; and, 

 of thousands examined, all bear the same appearance, and all are furnished with strong 



* " It ii< not to be understood, in making these distinctions, that these differences of form are so constant 

 that they can always be relied on ; for the form of the body varies, so that .the wingless mother may present 

 the more perfect oval of that destined to become winged." 



