176 



ridges in Grapta. The knobs seem adapted to this special 

 purpose, being fashioned something like a shirt stud, the 

 neck being a little narrower than the top. This top is 

 rounded, but on the anterior side a little pointed and pro- 

 longed, so that it makes an efficient hook to the liga- 

 ment, the other attachment of which (to the skin) is higher up 

 as the chrysalis hangs. Further examination, and sections 

 made after the larva has suspended, are necessary in this mat- 

 ter. When the skin is off, the chrysalis hangs limp and 

 greatly distended, in the shape of a long and nari'ow cone, ir- 

 regularly truncated at base. Presently the segments begin to 

 contract, those of the abdomen to an extreme degree, and to 

 widen correspondingly ; the head-case lengthens and the meso- 

 notum swells out, — - till in course of half an hour the charac- 

 teristic shape of the genus is assumed. 



DESCRIPTION OF THE PREPARATORY STAGES OF D. ARCHIPPUS. 



Egg. — Conoidal, the height being to the breadth as 70 to 

 60, and as 75 to 50, in different examples ; in some the sides 

 are much more convex than in others ; some hat flattened at 

 top ; the base flat ; marked by about twenty-two prominent, 

 smooth, vertical ribs, most of which extend from base to edge 

 of summit, but a few terminate a little below summit ; between 

 the ribs are about thirty smooth, horizontal striae, enclosing 

 spaces in shape of parallelograms Avith rounded corners ; the 

 surface within these spaces finely wrinkled in the direction of 

 the longer axis of the egg ; on the summit, about the micropyle, 

 are arranged six spaces, long, narrow, enlarged externally, each 

 with a deepened median groove running to the central point ; 

 these are separated, and between each pair are one, sometimes 

 two, similar spaces, but shorter and broader, each having a 

 double groove ; interior are two concentric rows of spaces like 

 these last, each double grooved ; the whole forming a sort of 

 rosette, with all the grooves leading to the micropyle ; color 

 greenish-yellow, becoming later grayish. Duration of this stage 

 from two to five days, according to the temperature. 



Young Larva. — Length 2.5 mm.; cylindrical, very little 

 largest anteriorly ; the head a little broader than next (second) 



