38 



SIXTH ANNUAL REPOKT 



the middle of summer, make themselves perfectly at home on the 



roots. 



Type Radicicola or Root-inuabiting.— We have seen that, in all 



probability, gallcECola exists only in the apterous, shagreened, 



non-tubercled, fecund female 

 form. Radicicola., however, 

 presents itself in two prin- 

 cipal forms. T h e newly- 

 hatched larva3 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 ac- 

 quire raised warts or tuber- 

 cles (7) which at once distin- 



tion of (<M;elliugs to leal-K^Ols, h,„1 ],„xvcr of ie?istin- S^lSn [Uem 11 Om gaUCBCOLa. 

 decomposition; ft, hirva sis it :t))iK';irs wlioiihibcniatiuir: t aI i i 4. r iU" 



r, d, antenna and k- of sanu ; e, f\ q, tomis of mm't^ In the development IrOm thlS 

 mature lice, h, jnaniilations of ikiii; i, Inbercle: J, . , ,. 



h-anaverse folds at bonlci- of joints; k, oimplo eye.s. pomt the tWO lOrmS are Separ- 

 able with sufficient ease : one {a) of a more dingy greenish yellow, with 

 more swollen fore-body, and more tapering abdomen ; the other (/3) of 

 a brighter yellow, with the lateral outline more perfectly oval, and 

 with the abdomen more truncated at tip. (8) 



The first or mother form (Fig. 5, f, g) is the analogue of ^aZZcecoZa, 

 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. I have counted in the 

 spring as many as two hundred and sixty-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 preg- 

 nancy this form becomes quite tumid and more or less pyriforra, 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 distinctly shagreened (Fig. 5, 7i,) 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, (9) 

 The eyes, which were quite perfect in the larva, become more simple 

 with each molt, until they consist, as in gallcecola, of but triple eye- 

 lets (Fig. 5, Z,',) and, in the general structure, this form becomes more 

 degraded with maturity, wherein it shows the affinity of the species 

 to the Coccidce, the females of which, as they mature, generally lose 

 all trace of the members they possessed when born. 



