68 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



with tho.se of C'itheroiiid mjidix. which tlK\v iiiost nearly resemble, those of Eacle-t imperiaJis 

 beiiij^ forkotl at the end, tiic Imlbims tips aie a little longei\ but still of the same general shape 

 and size. 



Along the aliiloiiiinal segments are six rows of very long and slender conical tuliercles (/'). giv- 

 ing rise each to a single black seta, which is about a third longer than the tul)ercle. There are 

 tluis eight setiferous tubercles on each segment (1-7), the lowest of which, one on each side, i.s 

 situated just above the base of the legs, and has a double base (r), sending off posteriorlv at 

 neaily right angles to the main tubercle a small lateral one, which emits a l)lack bristle. Tubercle 

 ■)! is also present, being about as high as / is thick at the base. On the eighth segment is a very 

 large, stout, acute, bright-red horn, which is borne either erect or directed a little forward. It 

 ends in two long, slender tubercles, each bearing a bristle about as long as the tubercle, and along 

 tiie trunk are several long spinose tubercles, each ending in a black bristle. The dorsal median 

 tul>ercle on the ninth segment is broader than long, being transverse, and bears two bristles. 

 The suranal plate is rather narrow, much narrower than long, and ending in two long, slender 

 tut)ercles, each bearing a dark bristle, besides four other bristles on the plate. The anal legs are 

 ])rovided with a dark patch on the side and bear below two long bristles, while there are three 

 black bristles on the Iwse of each middle abdominal leg. There are sixteen (possibly eighteen) 

 crochets on each of the abdominal legs. 



The body in general is pale green, with a slight yellowish tinge. There is a median linear 

 dorsal line along the body, and on each side are four narrow dark lines on a green ground, the 

 two middle lines being ditiuse and inclosing a dark band and bearing a row of bristles. 



The freshly-hatched larva spins a silk thread, which after a while is annoying to the o])server 

 from its being in the way and adhering to the leaves of its food plant. 



The larva, July 17. — Just before molting. Length, 7-9 mm. (fig. 2). Th(> head is now 

 small, black, one- half as wide as the body, which is tilled out from live days' feeding. The long- 

 est thoracic spines are scarce!}- one-third as long as the body, and all are pale I'eddish amber at 

 base and on tlie outer third, the terminal knobs being black-brown. The caudal horn is also pale 

 reddish andier at base. The dorsal tubercles of abdominal segments 1-7 bear a minute line at the 

 base behind. There is now a definite, broad, white lateral stripe along the abdominal segments 

 {not appearing on the thoracic), which is bordered above by a dark, thread-like, brownish, spiracu- 

 lar line, inclosing the spiracles, which are minute and difficult to detect. Above the spiracular 

 line is a linear distinct white line, and above this is the pale-green subdorsal stripe, ditlusely 

 i'dged on each side with a darker tint. There is a median, small, rounded, amber-colored, dor.sal 

 tubercle on the ninth segment, which is double, bearing two bristles. The end of the suranal 

 plate is reddish amber, bifurcate and ))earing black bristles (fig. 2). There is a dark ])atch on 

 the outside of the anal legs. 



Stagi' II. — Molted July 18 and IH. Length, 1(» mm. (fig. 3). The head is now high, 

 .slightl}' angular on the sides; black-ln'own with a light brown or greenish lateral stripe on each 

 side, diverging from the light-green vertex to the antenna', the two stripes varying from pale 

 brown to green. 'I'lie gicat spines (both thoracic and caudal) are of about the same proportions 

 and colors as in stage I, except that tiie eight thoracic spines, Avhich are still no shorter in pro- 

 portion to the body, being still one-third as long as the body, are not so much swollen at the 

 end, the bulb being shorter and broader and the spines larger, making a more decided fork 

 (fig. 3, (/), and thus resem))ling those of Eadev inywrlaHs. The setiferous tubercles on each seg- 

 ment are now rather large, conical, the two dorsal ones (/) large and stout, twice as large as the 

 subdorsal (//) and lateral ones, and all being lemon-yellow (less greenish than before), bearing a 

 terminal black spine, and with a second minute piliferous tubercle growing out from the side. 



The dorsal lines have almost disappeared, thei'e lieing a subdorsal, pale, almost whitish line, 

 besides a faint, narrow, dorsal, greenish line. The lateral ridge is now prominent and bright 

 lemon j'ellowish, forming a distinct l)roken line, bearing in the middle of each segment a very 

 slender, blackish, jiiliferous wart. A dark reddish purple, narrow, sj)iracular line. Between 

 this and the yellnw line is a white stripe and anuther narrower one above it, while still above is 



