NORTH AMKPaCAN LEPIDOPTKKA. 229 



figure of this species is not up to his usual work iu this line. The 

 difference in shape of the outer margin is marked and rather unusual. 

 A 9 ill my collection agrees with viyops in every particular ; a % 

 from the same brood also in my collection has the margin entire and 

 not at all angulate. My specimens are both perfect. Other speci- 

 mens which I have seen are more or less intermediate. It is in all 

 an easily recognized species. 



The life history is very imperfectly known. Mr. Strecker de- 

 scribed the larva in general terms from a figure " in which it is rep- 

 resented as being 1 i to 2 inches in length ; of a pale green color, 

 beautifully variegated with dorsal and lateral yellow and red stripes 

 and spots, somewhat iu the manner of S. mi/ops." Mr. Peck, in 

 " Can. Ent." viii. 239, says : " A characteristic of astylus is its caudal 

 horn, which is armed with two spines at its tip, appearing bifurcate 

 at first glance. These spines are constant from its hatching. Color 

 of horn, dark brown at tip and base ; pale green at tip and centre, 

 pointing forward." At the last molt this dark brown fades to an 

 extremely light shade. It feeds from six to seven weeks, and the 

 consequent exposure to parasitic attack may in some measure account 

 for its rarity. The food plants are Vaccinium corymbosum, liomcea; 

 and low Huckleberry (Fernald). 



<^RESSO]VIA G. & E. 



Pr. E. S. Ph. V. 161 ; id. 186. 



Head small, sunken, larger, somewhat more prominent in the male, 

 iu which also the eyes are globose. The vestiture is hairy, forming 

 a frontal ridge between the antennjie. Palpi rather slender, the ves- 

 titure rather rough, directed forward, divaricate at tip, terminal joint 

 minute. In the male they ar-e unusually long, often considerably 

 exceeding the vertex, while in the female they scarce reac-h the mid- 

 dle of the front and are not so stout ; all intermediate forms are 

 found. The tongue is rudimentary. Antennie rather short, fusi- 

 form, in the male doubly bipectinated, the branches ciliate, becoming 

 shorter to the tip. As in the Saturnii(he there are two branches to 

 each side of each joint, and the branches join in i)airs at their tips. 

 Unlike Satarnia (used iu its broadest sense), however, the two 

 branches of the same joint ai)i)roach at tip instead of the anterior 

 of one joint to the posterior of the next. In the females the an- 

 tennae are simple. Thorax short and stout, sub(puulrate ; vestiture 



