83] LEPIDOPTEROUS LARVAE — FR ACKER 83 



Trichostibas parvula Edwards. Crochets in a mesoseries; beta 

 caudad of alpha on abdominal segments 1 to 8, dorsocaudad of alpha on 

 segment 9; Pi group unisetose on segments 2, 7, and 8. 



Family Gelechiidae 



The enumeration of Gelechiidae in Dyar's List is considered as 

 very nearly correct and will be followed more closely than is possible 

 with most other families of Microlepidoptera. Larvae of this family 

 will be most often confused with Pyralididae and Tortricidae on account 

 of similarity in size and habit. The distinctly trisetose Kappa group 

 of the prothorax will differentiate from the former and the distance of 

 setae beta on segment 9 will distinguish from the latter. It seems un- 

 necessary to enumerate such characters as the location of all the setae, 

 for the larvae are typical Micros, any important differences from the 

 usual plan (Figs. 39-42) being noted in the tables. It might be men- 

 tioned in addition that the crochets are biordinal except in a few degen- 

 erate eases, that the front and adfrontals are very acute above, the ad- 

 frontals often reaching the vertical triangle, that the spiracles are cir- 

 cular in outline, those of segment 8 usually being larger and higher on 

 the body, and that the ocelli are almost never arranged as described 

 for Oecophoridae (cf. Figs. 80 and 81). 



The following synopsis of the genera is incomplete, owing partially 

 to lack of material, but is an arrangement which can be developed fur- 

 ther as the larvae of more species become known. 



a. Crochets wanting or reduced and rudimentary; no proleg swellings 

 present ; thoracic legs small, 

 b. Body swollen and strongly tapering at ends. Metzneria 



bb. Body nearly cylindrical, scarcely tapering. Sitotroga 



aa. Crochets present and well developed. 



b. Crochets of ventral prolegs in a complete circ'e, usually biordinal; 

 those of anal prolegs in a continuous transverse series, 

 c. Prolegs long and slender ; crochets few ; setae rudimentary ; head 

 retractile. Nealyda 



cc. Prolegs short and stout, crochets usually numerous. 



d. Setae rho of segment 8 cephalad, rarely cephalodorsad of spi- 

 racle; body always striped; setae large. 

 e. Abdominal segment 7 with setae beta closer together on 

 dorsum than setae alpha ; segment 8 with setae beta far- 

 ther apart than setae alpha. Arogalea 

 ee. Segments 7 and 8 both with setae beta farther apart than 

 setae alpha. 



