86 ILLINOIS BIOLOGICAL MONOGRAPHS [86 



Family Blastobasidae 



The larvae of this family are very similar to the last two discussed 

 but a few differences remain. Rho, on abdominal segment S, is caudo- 

 dorsad of the spiracle, while kappa is cephaloventrad, an arrangement 

 found in no other larvae. The prolegs are short and bear a complete 

 series of uniordinal crochets, which are, however, sometimes irregular. 

 Only primary setae are present on the body. Ocelli indefinite in speci- 

 mens examined. 



The species seen were : Valentinia glandulella Riley and Holcocera 

 gigantella Ch. of North America and Endrosis lacteella of Europe. 



Family Cosmopterygidae 



Head more or less depressed, very much so in Cosmopteryx, small, 

 retractile within prothorax ; adfrontals not quite reaching vertical tri- 

 angle ; ocelli all close together, seta vii closest to second ocellus, fourth 

 ocellus usually as close to sixth as to fifth. Setae of body small ; abdo- 

 men with kappa and eta adjacent; setae beta of segment 9 much farther 

 apart than each is from alpha of that side, beta, alpha, and rho in a 

 transverse line. Thoracic legs with coxae twice as far apart as wide ; 

 prolegs far apart, each bearing a complete circle of uniordinal (Stilbo- 

 sis) or biordinal crochets. 



The following species were examined : 



Cosmopteryx gemmiferella, C. clandestinella, 



Limnoecia phragmitiella, 



Homalcdra sooalella, H. heptathalama, and 



Stilbosis tesquella, of America, and 



Cosmopteryx scribalella, 



Heydcnia fulvigutella, and 



Laverna phragmitella of Europe. 



SUPERFAMILY PYRALIDOIDEA 



Scarcely half a dozen characters are common to all the larvae 

 within this superfamily. The deciding factors are the presence of a 

 bisetose Kappa group on the prothorax and the close association of kappa 

 and eta on the abdomen. Some of the Pterophoridae have these points 

 obscured by secondary and tufted setae, and such incidental structures 

 as the circular spiracles and the long slender prolegs must be used in 

 determination. (Figs. 47, 48, 61.) 



Unless care is taken in observing the number of setae on the pro- 

 legs, Lacosoma will trace to this superfamily. It is distinguished from 

 Pyralidoidea by the Pi group which consists of from four to eight setae. 



