108 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



wings broad and distinct. Underside as above, but no paler; the outer edge of the fore wings 

 is deeper lilac than above, though becoming dark oeheroiis toward the inner angle. There is 

 little difference in tlie number and distribution of the strigse. 



9 , fore wings paler, thinner in the middle than in 9 stigma., and it is a rather smaller moth; 

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

 spot is the same. The body and wings paler ocherous. Hind wings with the extradiscal line 

 obsolete above, but fairly distinct below. In shape they are exactly as in ^1. xfic/t/ni. 



Expanse of the fore wings <? , 43 mm.; 9 , .50-5-1: mm. Length of a fore wing <? , 22 mm.; 

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

 14 mm.; 9 , 15-17 nmi. Breadth of hind wing S , 11 mm.; 9 , 11-13 mm. 



J^gg. — "'August 1, 1869, received of F. A. Gates, Massillon, Cedar County, Iowa, a rilibed 

 female of Dri/ocampa senatoria witii a batch of over 300 eggs on the imderside of a raspberry' 

 leaf. These eggs are almost round in outline, depressed, being about half as high as wide, the 

 width across l)eing 0.04 of an inch. The shell is so \erx transparent that it makes a very good 

 ol)ject for watching the development of the emVjryo. The egg when tirst laid is yellow, with a 

 darker brownish ring above." — (Riley). 



Riley states that the female lays a batch 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. Tiie eggshells are \ev\ thick, transparent as glass, and if the 

 young caterpillars have left the eggs, the emptj' shells look like iridescent glass." 



The larva? hatched August 1 and 2. 



Stagt I. — Length. 3.5-4.5 mm. 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 unarmed, no spinules visible vnider a lens. The spines on the other 

 segments are black, being of the same color as the thoracic legs. The body is ichoUy greenish 

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



The end of the body is a little more yellowish than toward the head. 



Thoracic legs dark; abdominal 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 body. The two median setue on segment 8 arise from a 

 common base, but are nuich as in A. ruhteimda, Stage I. (See PL LI, tig. 3; LHI, tig. 1.) 



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

 yellow tints, and the two horns are hJacl'. The head is scarcely as wide as the body, and the hairs 

 are greener and less conspicuous. 



Stage II. — August 10-12. Length, 7-8 nmi. Ilead^ jirothoracic segment above and horns, 

 urdh the svi'iiniil plate and anal legs jetd>lacl\ The prothoracic shield is now present and black- 

 pigmented around the edge and along the middle (tig. 3 a). The body is now daA' green v:ith 

 yelloioish-green lateral lines andhlach conical acute icarts. A median dor.^al dark line; a suhdorsal 

 pale yelIoirish-gree7i line, and heleno it a lateral wider line of the same hue, separated hy a very 

 narrow dark-green line from a hroad lateral line which includes the lateral swollen ridge, and a 

 row of conspicuous black tubercles. Under side of body dark green. The tubercles on the 

 eight and ninth segments larger than those in front. Suranal plate rough, tuberculated, the two 

 terminal spines being 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, nearly' twice as long as the body is wide, and one-third longer than the head is wide; 

 they are now finel}- spinulated, and less bifid at the end than in Stage I. Thoracic legs black; 

 abdominal feet dark green, except the anal pair, wliich are black. 



