NORTH AMERICAN EUCOSMINAE. - 9 



cidae on gentitalia, which alone enable clear and exclusive definition 

 of the two families, and on genitalia the Olethreutidae are distinctly 

 in advance of the Tortricidae. The genitalia of the Olethreutidae 

 with the peculiar fusing of the upper margin of saccalus to the costal 

 edge of the harpe leaving a restricted opening toward the base of 

 the harpe, the narrowed articulating base of the harpe, articulating 

 against the juxta of the anellus and connecting with the tegumen 

 only by the costal hook, or (as in Rhyacionia) by a thin membrane 

 from the place usually occupied by the hook, rather than the primi- 

 tive articulation along the lateral margin of vinculum, as well as the 

 loss of transtilla and the progressive reduction and elimination of 

 many fundamental structures all indicate a specialized and advanced 

 type. From this no generalized type could have developed, and in 

 every way the Tortricid genitalia are distinctly the more generalized 

 type. The genitalia of the Olethreutidae are unique and like those 

 of no other group in the Lepidoptera. Indeed it is hard to see just 

 where the connection is made between the two families, so complete 

 is the break. At any rate, it is far back, and one thing is certain, the 

 Tortricidae could have developed from no group with the genitalic 

 development of the present Olethreutidae. Exactly reversing Mey- 

 rick's order I would derive the Olethreutidae from the Tortricid 

 stem, interpreting the Laspeyresiinae as their most advanced develop- 

 ment. The Olethreutidae as a whole are a newer more plastic group, 

 with structural characters unsettled, generic limits poorly defined, 

 and many species in process of change. From it no other family 

 has as yet developed. 



The tree (facing p. 1) illustrates my present conception of the phy- 

 logeny of the genera of the Eucosminae and the relation of the 

 larger groups of the Olethreutidae to each other and to the Tor- 

 tricidae. 



Family OLETHREUTIDAE. 



Moth. — Antennae less than two-thirds as long as fore wings. 

 Head rough scaled above. Labial palpus ascending, with third joint 

 porrected and normally short. Ocelli present. Tibiae with all spurs 

 present. Fore wing with eleven or twelve veins; 1 bifurcate; 2 

 from cell before outer three- fourths ; 4 and 5 sometimes connate; 

 7 and 8 separate, stalked or united; other veins separate. Hind 

 wing with 7 or 8 veins ; 3 and 4 separate, connate, stalked or united ; 

 6 and 7 approximate towards base or stalked, rarely separate and 

 parallel {Dichrorampha) ; 8 free; lower median vein pectinate towards 

 base. Harpes of male genitalia strongly chitinized ; basal articulation 

 narrow, articulating against basal plate (juxta) of anellus; sacculus 

 not extending into a free arm but with upper edge fusing with costal 



