91] LEPIDOPTEROUS LARVAE — FRACKER 91 



Vitula edmandsii Acrobasis betulella 

 Mineola indiginella (a) A. comptoniella 



31. amplexella (b) A. stigmella Dyar 



Tacoma nyssat colt lla Canarsia ulmiarrosorella 



Crambinat . The larvae of many species of Crambus are of economic 

 importance and should be familiar to entomologists. They can not 

 readily be differentiated from each other, but can be distinguished from 

 other groups. Any larva with a complete circle of triordinal crochets, 

 with but two setae in front of the prothoracic spiracle, with a single 

 seta on segment 9 caudad of the spiracle on segment 8 and with but one 

 seta at the base of each mesothoracic leg, is a crambid. In addition 

 there are a few species which closely resemble Pyraustinae. Crambus 

 trisectus, Chilo prejadellus, and Dicymolomia julianalis, together with 

 a large number of unidentified species of Crambus, were examined. 



Pyraustinae. The penellipse of crochets which characterizes this 

 subfamily varies in extent from a semicircle to an almost complete 

 ellipse. Other subfamilies are entirely distinct, except a few Crambinae, 

 most of which have biordinal crochets. 



Genera of Pyraustinae : 



a. Front extending three-fourths, adfrontals nearly or all the way, to 

 the vertical triangle, 

 b. Kappa on eighth abdominal segment located directly dorsad of eta ; 

 first ocellus much larger than others. Hellula 



bb. Kappa on eighth abdominal segment located caudodorsad of eta; 

 first ocellus not much larger than others, 

 c. Adfrontals not strongly widened above, their lateral margins 

 rather regularly convergent ; head normal in size. 

 d. Head not bilobed above, except slightly in some species, 

 e. Spiracles elliptical in outline, heavily chitinized, normal in 

 size ; body with black pinacula and sometimes black stripes. 



Loxostege 

 ee. Spiracles circular in outline, slightly chitinized, very small ; 

 body decorated with transverse red stripes. Eustixia 



dd. Head conspicuously bilobed above, with the epicranial suture 

 forming a deep groove between the lobes; head black, body 

 marked with conspicuous black and white spots. Thoh ria 

 cc. Adfrontals strongly widened above so that their lateral boun- 

 daries appear to be parallel to each other for the ventral three- 

 fourths of their length: head very small. Cybalomia 



