108 MEMOIRS OF THE NATIONAL ACADK.MV OF SCIENCES. 



wings broad iiiid distinct. Underside as above, but no paler: the outer ed<>e of the fore wings 

 is deeper lihic than above, though becoming dark oeherous toward the inner angle. There is 

 little difi'erence in the number and distriltution of the striga^ 



9 , fore wings paler, thinner in the middle than in 9 sfu/ina, and it is a rather smaller moth; 

 the wings are less strigated or speekled, the specks being fewer and less distinct. The discal 

 .spot is the .same. The bod\- and wings paler oeherous. Hind wings with the extradiscul line 

 obsolete above, l)ut f.iirly distinct below. In shape they are exactly as in A. xtignia. 



Expanse of the fore wings ^, 43 mm.; 9, 50-54 mm. Length of a fore wing ,?, 22 mm.; 

 9 , 24—26 mm. Breadth of a fore wing S , 10 mm. ; 9 , 13-15 mm. Length of hind wing S , 

 14 mm.; 9 , 15-17 mm. Breadth of hind wing ^',11 mm.; 9 , 11-13 mm. 



Egg. — "August 1, 1869, received of F. A. Gates, Ma.ssillon, Cedar County. Iowa, a ri})bed 

 female of Dryocampa senatorla with a l)atch of over 300 eggs on the underside of a raspberry 

 leaf. The.se eggs are almost round in outline, depressed, being about half as higii as wide, the 

 width across being 0.04 of an inch. The shell is so verj- transparent that it makes a very good 

 object for watching the development of the embryo. The egg when first laid is yellow, with a 

 darker l)rownish ring above." — (Riley). 



Riley states that the female lays a })atch of over 300 eggs, in the case observed, on the under- 

 side of a raspberry leaf. 



Lugger found from 350 to 675 eggs in a cluster. He says they are very beautiful objects, 

 "•both when fresh and after having hatched; in the former case they are of a pale green, and 

 change later to a golden brown. The eggshells are very thick, transparent as glass, and if the 

 young cater])illars have left the eggs, the empty shells look like iridescent glass." 



The larvic hatched August 1 and 2. 



Stage I. — Length, 3.5-4.5 nmi. Head large, round, smooth, wholly black, a little higher 

 than wide; when seen from in front a little wider than the body. Prothoracic segment a little 

 wider than the second thoracic segment; smooth, unarmed, but with a transverse dusky patch 

 extending across it. The second thoracic segment bears a pair of high smooth clavate spines or 

 horns which are a little longer than the head is wide and each bearing two terminal bristles of 

 equal length. They are vinarmed, no spinules visible under a lens. The spines on the other 

 segments are ])lack, being of the same color as the thoracic legs. The body is vliolhj greenixli 

 ycllov\ with long, rather pale, yellowish-brown hairs arising from conical tubercles. 



The end of the body is a little more yellowish than towai-d the head. 



Thoracic legs dark; al)dominal legs all of the same color as the body. Suranal plate smooth, 

 pale, not granulated; the two terminal spines minute, weak; the plate is soft, thin, not pigmented, 

 anal legs pale, like the rest of the bod}-. The two median setaj on segment 8 arise from a 

 common base, but are much as in ^1. riihtcunda. Stage I. (See PI. LI, fig. 3; LIII, tig. 1.) 



August 4 the same larva- had become 5.5 mm. in length. The body was now green, with no 

 yellow tints, and the two horns are hJ<icl\ The head is scarcely as wide as the Ijody. and the hairs 

 are greener and less conspicuous. 



Stage If. — August 10-12. Length, 7-8 nmi. Head., j>rothoravie mgment above and horns, 

 with the suranal phde and anal legs jet-hlacl:. The prothoracic shield is now present and black- 

 pigmcnted aroimd the edge and along the middle (tig. 3 <i). The body is now darl' green with 

 yellowish-green lateralllnes andhlaeh conical acute irartx. A iiiedl<tn <li)rs(d dark line ; a subdorsal 

 pale yeUoiolsh-green line, and Ixhur It a lateral irld<r line of the sarlie hue, separated l>y a very 

 1} arrow darh-green linefroai a hrnad lufi ral 11 m a-hicli l/tdudes the lateral s^collen ridge, &nA a 

 row of conspicuous black tubercles. Under side of bod3' dark green, The tubercles on the 

 eight and ninth segments larger than those in front. Suranal plate rough, tu})erculated, the two 

 terminal spines l)eing now large and prominent, black; it is much specialized and pigmented, 

 while the two terminal spines are several times larger than in Stage I. Thoracic horns large, 

 long, black, nearl}' twice as long as the body is wide, and one-third longer than the head is wide; 

 they are now finely spiiudatcd, and less l)ifid at the end than in Stage I. Thoracic legs black; 

 a))doiiiina] feet dark green, except tiie anal ))air, which are black. 



