112 ZYGJEyiDJE AND BOMBYCID^ 



BOMBYCIDJE. 

 BOMBYCINS. 

 Genus GASTROPACHA. Ochsenheimer. 



Head prominent, smooth. Front long, twice as long as broad, ob- 

 lique. Palpi stout, long, porrected, greatly exceeding the front, giving 

 to the head the appearance of a beak. Antennae short, stout, finely 

 pectinated to the tip in the $ , somewhat pectinated in the $ . Abdo- 

 men hairy, stout, tufted in the $ , somewhat exceeding hind wings. 



Anterior wings with the costa straight, convex at the apex; outer 

 margin rounded, dentate; anal margin rounded, somewhat emarginate, 

 frequently very strongly so ; inner margin straight, about equal in 

 length to the outer margin. Costal vein long, reaching nearly to the 

 tip. Subcostal vein five-branched ; first originates very near the base, 

 going rapidly to the costal vein; second originates at the middle of the 

 wing, forking near the apex, one branch going to the costa, the other 

 to the outer margin ; third originates near the second ; fourth and fifth 

 spring from a common stalk as long as the distance between second 

 and third. Median vein with four very long nervules; first and second 

 arise at the middle of the wing ; fourth very near the base ; third mid- 

 way between second and fourth, 



Secondaries with the angles and outer margin strongly rounded, 

 dentate, generally with a deep emargination on the costa near the apex, 

 the base of the costa which is much rounded, projecting in advance 

 of the costa of the primaries when at rest. Costal vein very distant 

 from the costa throwing off at right angles five small veins towards the 

 costa which are suddenly bent outward as they approach the costa, 

 the main vein being furcate at the outer third. Subcostal vein short, 

 forking inside the middle, and previously throwing off a short transverse 

 branch, which enters the costal vein just before its bifurcation. Median 

 vein four-branched, nervules very long, third nearly as far from second 

 as from fourth ; first and second with a common origin. 



The species of this genus are difficult to tabulate. It has a wide 

 o-eographical range, extending from the Atlantic to the Pacific Coast, 

 and from Alaska to southern California, the species from the Pacific 

 Coast being of small size. The larvse are not gregarious. 



