146 PROC. ENT. SOC. WASH., VOL. 23, NO. 6, JUNE, 1921 



In the lepidopterous genitalia all or most of the following nine 

 external structures are present and can be differentiated and 

 definitely homologized in the various groups however modified 

 they may be. 



Vinculum (Vm). 



The vinculum is a ventral chitimzed band articulating at its dorsal extremi- 

 ties with the tegumen. It is usually a simple narrow band but may be divided 

 in the middle ventrally (ex. Ellopia) or extended into an anteriorly projecting 

 process (ex. many Gelechiidae and Plutellidae). This and the following four 

 structures are formed from sclerites of the ninth abdominal segment. 



Anellus (An). 



The anellus is a small, more or less triangular plate situated within the ven- 

 tral angle of the vinculum and supporting the aedoeagus. This support may 

 be affected in various ways; the anellus may be a mere plate with a hole (ex. 

 Hemerophila) or smuation in which the aedoeagus rests (ex. Xyloricta); or it may 

 partially surround the aedoeagus as a chitinous cylinder (ex. Cerostoma) or semi- 

 cylinder (ex. Eorkhausenia conia) or from the plate an arm may be developed 

 on which the aedoeagus is supported and pivoted (ex. Olethreutidae). In some 

 forms the anellus develops various projections or lobes (ex. Ethmiidae, Steno- 

 miidae). Sometimes the structures are not differentiated, the aedoeagus pass- 

 ing through the unchitinized membrane (ex. some Helialidae}. 



Aedoeagus (Ae). 



The aedoeagus is normally a tube containing and protecting the penis, some- 

 times so modified as to be merely a ring with a thin extension (ex. many Blasto- 

 basidae) or more or less split and occasionally developed into finger or thorn-like 

 projections from a tubular base (ex. Gelechia natalis). It articulates on the 

 anellus when the latter is present. Sometimes, however, it is merely supported 

 by the membrane of the 9th segment. It may be simple or prolonged into one 

 or more spines or processes at apex (ex. Gelechia and Stenoma) or be laterally 

 armed with tooth-like projections (ex. Hystricophora}. Often the posterior end is 

 produced beyond the entrance hole of the penis into a blind sack (ex. Tortricidae, 

 Plutellidae, etc.). Some authorities have considered the aedoeagus to be but 

 a chitinized part of the penis proper and therefore strictly speaking an internal 

 structure; but we consider it a part of the external structure. As a chitinized 

 part it has always a definite beginning and ending, is always rigid and serves 

 directly as a protective armature and guide to the membranous penis. 



Within and for part of its length connected with the aedoeagus lies the penis 

 (P), a soft flexible tube which can be projected by blood pressure far beyond the 

 mouth of the aedoeagus itself. It is usually armed near its tip by one or more 

 spines or thorns, the so-called cornuti (Cn) (of Pierce) or "love thorns" (of Roth- 

 child and Jordan). The number, size and shape of these is constant within the 

 species and of great aid in specific differentiation. 



Harpes (Hp). 



The harpes are paired lateral clasping organs attached to the vinculum ard 

 frequently also articulated on the anellus, occasionally fusing at their base (ex. 



