No. 1. 



BOMBYCLNE MOTHS OF NORTH AMERICA— PACKARD. 



101 



thia stage. The subdorsal spines are about as long as the body is thick, the dorsal ones a little thicker and longer; 

 they end in usually fine setae, one of which is finely barbed about as long as the spine itself. Both the subdorsal and 

 dorsal spines of the three thoracic and of the eighth and ninth abdominal segments are deeply forked, the forks of 

 equal length and each bearing the long bristle as well as four or five short ones. Those of the other segments are not 

 forked. The first thoracic dorsal and subdorsal spines are as long and large as those on the two hinder segments. The 

 spines are represented in figure 6. 



Figure 2 represents the freshly hatched larva, drawn with the camera, with the lateral, eversible glands (g). 



Figure 3 represents the armature of the three thoracic segments. Pp, the prothoracic shield; I, II, III, the bifid 



Fig. 4. — Automeris io. Armature of the last thoracic and abdominal segments, 1, 2, ft-10, stage I. 



dorsal spines of the three thoracic segments, about three-fourths or four-fifths as long as the segments are thick; sd', 

 sd", id"', the bifid subdorsal spines; s', s" , s"' , the spiracular spines; the prothoracic ones throw off a bristle near the 

 middle; in those behind this bristle is wanting; they are inserted just in front of the spiracle, the corresponding ones, 

 however, on the abdominal segments being situated just below the spiracles; i', i" , V" , the small infraspiracular 

 spines which are about half as long as the Bpiracular ones; V ', I", V" , insertion of the thoracic legs. 



Figure 4 represents the armature of some of the other segments. A, the third thoracic and the first and second 

 abdominal; III, V , II", the dorsal spines; and the other lettering as before; sp, the spiracle; g, the lateral eversible 

 gland of the first abdominal segment. B, the sixth to tenth (and last) abdominal segments; faint traces of the spiracular 



and infraspiracular yellowish lines are to be seen, hence the medio- 

 dorsal, the subdorsal, and the two lateral longitudinal lines of the 

 larva in its second stage are already indicated in the first stage. The 

 abdominal legs each bear eight ungues, or four on each side; and all 

 except the anal legs bear a piliferous wart just above the planta; 

 sp, the rugose suranal plate, bearing five piliferous warts on each side; 

 lp, the lateral plate of the anal legs, with three or four piliferous warts. 

 Stage II. Length, 7 mm.; width of head 1.3 mm. The head is 

 chestnut-brown. The body is uniformly reddish umber-brown; the 

 spines are blackish brown, with the spines black at the tip. The 

 dorsal and subdorsal spines are now approximate in shape to those of the 

 last stage, being bulbous at base, and with radiating stout spinules, but 

 the latter are less in number than in the fifth and sixth stages. The dorsal 

 spines of the prothoracic segments are bifid, the forks of the same 

 length, and each bearing a long hair; along the trunk are pale 

 scattered tubercles, each ending in a long hair. The second thoracic 

 dorsal spines have but one terminal piliferous spinule and a single 

 lateral one, the other spinules ending in a sharp black point. The 

 third thoracic is like all the abdominal dorsal spines which bear radiating spinules, not ending : n a single piliferous 

 spinule, as in figure 9, vi. 



Figure 5, sd"', represents a spine of the subdorsal series, the one figured being that on one side of the third thoracic 



segment, but those on the abdominal segments (except x) are like it, though most of the abdominal ones have two or 



three small tubercles near the base which bear barbed bristles, as at sd"i. All the long setse bear a few minute barbs. 



In stage IV (?), when the larva is 20 mm. in length, the prothoracic dorsal spines are nearly twice as long as the 



second thoracic; the latter, however, have more spines at the base than those in front, and the lateral terminal are a 



Fig. 5.- 



-A utomeris io. Armature of the sixth abdominal 

 segment, stage II. 



