40 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I46 



organ, aedeagus and parameres, therefore, is supported on the poste- 

 rior margin of the ninth sternum. When the parameres are sepa- 

 rated from the aedeagus, they appear to be independent appendages 

 of the ninth sternimi, and have been regarded as such. The fact, 

 however, that the parameres always originate as lateral branches of 

 the genital rudiments shows that their lateral position results from 

 a secondary displacement giving them a mechanical advantage as in- 

 dependently movable clasping organs. The subsequent division of the 

 parameres into "coxites" and "styli" occurs secondarily and only in 

 the higher orders. It seems desirable, therefore, to adopt a nomen- 

 clature free from unproven hypothetical assumptions of dubious 

 validity. 



The genital claspers need no other name than that of parameres 

 (side parts), a name first given to them in the Coleoptera. The 

 two segments have been called the "basimere" and the "telomere," 

 which terms to be specific should be basiparamere and teloparamere. 

 When the distal segments resemble grappling hooks they have ap- 

 propriately been called harpagones (sing, harpago). The median or- 

 gan that gives exit to the ejaculatory duct is best termed the aedea- 

 gus (g. V.) because the word means simply the principal genital part. 

 By the dipterists it has been called the mesosome, by others the phallus 

 or phallosome, or more generally the penis. Since the functional 

 intromittent organ is usually the everted membranous inner wall 

 of the aedeagus with the gonopore at its tip, this structure is more 

 literally a penis. 



The name phallus is not inappropriate for the medium genital 

 organ alone, but the latter has for so long been known to entomolo- 

 gists as the aedeagus that this term has entomological priority, and 

 the insect organ has no homologue even in other arthropods. The 

 word "phallus" in ancient Greek was a vertebrate term and was spe- 

 cifically applied to an artifact, symbolical of generation, carried in 

 certain processions. 



Since we seem to lack a good general name for the genitalia of 

 the insects, the writer (1941) has suggested that the term phallus 

 might, consistent with its original meaning, be applied to the entire 

 genital structure developed from the primary rudiments. The word 

 combines euphoniously with prefixes and suffixes. The aedeagus and 

 parameres are often not separated at their bases, in which case the 

 three parts form a phallic unit with a common phallobase. The 

 eversible inner tube of the aedeagus which serves as the functional 

 penis of the insect may then be termed the endo phallus (more 



