44 U.S. NATIONAL MUSEUM BULLETIN 244 



sclerites entire, broadly triangular; ventral sclerites much reduced, 

 divided longitudinally into pair of slender, curved plates. 



Primaries with R5 absent (possibly fused with R4) ; all veins separate 

 from cell except M2 and 3, which are stalked; base of media undivided 

 in cell of both wings; cubitals directed somewhat posteriorally ; anals 

 reduced with 2A alone appearing as distinct vein to wing margin. 

 Secondaries with all veins separate; no connecting vein between 

 Sc+Ri and Rs. Wing expanse 12-14 mm. 



Male GENITALIA. — (Fig. 246.) Relatively weakly sclerotized. Apex 

 of tegumen with shallow depression. Valves with basal area un- 

 developed; sacculus with small apical spines. Vinculum triangular, 

 without distinct saccus. Eighth sternite (fig. 191) base almost com- 

 pletely divided, furcal arms very long, slender. 



5. Prochalia Barnes and McDunnough 



Prochalia Barnes and McDunnough, Contr. Nat. Hist. Lep. N. Amer., vol. 2, 

 no. 4, p. 171, 1913; Check List Lep. Boreal Amer., p. 125, 1917. — Gaede in 

 Seitz, Macrolep. World, vol. 6, p. 1179, 1936.— McDunnough, Check List 

 Lep. Canada and USA, pt. 2, p. 103, 1939. 



Type op genus. — Prochalia pygmaea Barnes and McDunnough, 

 1913. Monobasic. 



Male. — Antennae broadly bipectinate, pectinations arising from 

 apical portion of each segment. Foretibia (fig. 172) with long epi- 

 physis, nearly equalling tibia in length. Middle tibia with single apical 

 spur. Posterior tibia unarmed. 



Forewings (fig. 153) usualh^ 12-veined, may be reduced to 9 because 

 of a fusion of one or more radials and loss or fusion of medial. R4 and 

 Rs usually stalked, rarely completely fused ; medial veins separate, with 

 rare possibility of reduction in number; intercalary cells absent from 

 discal cell of both wings; anal veins as in Crypiothclea with spur of 3 A 

 usually, but not always, present. Secondaries usually 8-veined with 

 reduction to 7 because of loss of medial vein; oblique crossvein con- 

 necting Sc+Ri and Rs absent. 



Male genitalia. — Elongate. Valves with pulvilli obsolete; apex 

 of sacculus minutely spined. Aedeagus simple. Eighth sternite 

 (fig. 192) with slender furcations somewhat longer than base. 



Female. — Vermiform with all external appendages vestigial. 

 Head and dorsal area of thorax slightly sclerotized. 



Female genitalia. — ^(Fig. 299.) External genitalia almost en- 

 thely membranous, extremely reduced. Internally, ductus semi- 

 nalis quite short, less than bursa in length, bursa itself smaller than 

 spermatheca in length and volume; duct of spermatheca long, ap- 

 proximately 2-3x that of seminal duct. Accessory glands apparently 

 lacking. 



