16 U.S. NATIONAL MUSEUM BULLETIN 244 



were noted. These involved merely the connate condition (versus 

 typically stalked) of M2 and 3 in the hindwing. 



Legs: Several important characters are to be noted in the legs of 

 these moths. The armatm-e of the tibiae is one of the more obvious, 

 which, imfortunately, has been neglected largely by a number of 

 earlier workers. The presence or absence of the epiphysis or of the 

 small tibial spurs occasionally provide absolute species characters (as 

 in 0. platensis), and frequently these are correlated with other charac- 

 ters in order to aid in defining genera. The condition of the epiphysis 

 (or the spurs of the tibiae) should not itself be considered a firm basis 

 for generic separation as some authors erroneously have believed in 

 the past. Examination of the interspecific variation of this structure 

 as it occurs in such genera as Solenobia, Hyaloscotes, and Oiketicus 

 should make this evident. 



Leg ratios, involving usually the relative lengths of the tibia and 

 tarsal segments, often can be rather useful. Characters of this sort 

 have been applied in the erection of the new subgenus Paraoiketicus. 



Tarsal claws may be of considerable taxonomic importance (Clench, 

 1959). In the American forms, however, no divergences were noted 

 from the smoothly ciu-ved and simple condition except for relatively 

 minor interspecific differences with regard to size. 



Abdomen: The main systematic importance of the abdomen lies in 

 the structure of the abdominal sclerites, particularly the last (eighth) 

 sternite. This is frequently of specific importance, but, like so many 

 other characters, it varies, and so it should be used with the usual 

 degree of taxonomic discretion. In the specific descriptions of this 

 study, the eighth sternite has been discussed in connection with the 

 male genitalia since these structures are closely associated in life and 

 frequently in slide preparations. 



Genitalia: The copulatory organs of the male offer only limited 

 possibilities for specific and generic delimitation in this family, as 

 contrasted to their great significance in many groups of Lepidoptera. 

 In some genera (e.g., Cryptothelea) the genitalia can be relied upon in 

 delimiting the genus, but for many psychids of both hemispheres 

 species belonging even to different genera scarcely can be distinguished 

 on the basis of this apparatus alone. This convergence of structure 

 may be due in part to the very similar mating habits of the members 

 of this family. 



Female. — In the more primitive psychids, various specializations 

 have not advanced as far as in the higher members of this family. 

 In most of the lower forms the female has retained the antennae, 

 functional legs, and a normally sclerotized body wall with the result 

 that specific or at least generic boundaries can be determined. 

 Furthermore, the ovipositor is reasonably elaborate and similar in 



