510 PROCEEDINGS OF THE NATIONAL MUSEUM vol. lu 



(jx, fig. 2), the ventral plate of the anellus, is normally absent. It 

 occurs in a reduced or rudimentary form in several species. 



The manica (ma, fig. 2) is the eversible, membranous sheath of the 

 aedeagus. In the Acrolophidae, it encloses most of the unopened 

 portion of the aedeagus, articulating with both the aedeagus and the 

 anellus. Since the manica is unsclerotized, unarmed, and rather 

 obscure in the members of this family, it offers no character of taxo- 

 nomic value and it is not mentioned elsewhere in this revision. 



The aedeagus (ad, figs. 2, 6) is a sclerotized tube supported by the 

 membrane (anellus) of the ninth segment. Its base is normally 

 somewhat expanded or bulblike, and it may be simple or prolonged into 

 one or more spinelike processes at the apex. It may be glabrous or 

 armed with toothlike projections or spines. This rigid cylinder serves 

 as a protective armature and guide for the membranous penis (pn, 

 figs. 2, 6) , an internal genital structure. Although the penis lies within 

 and for part of its length is connected with the aedeagus, this soft and 

 flexible tube can be projected by blood pressure far beyond the mouth 

 of the aedeagus itself. This eversible portion of the penis is called the 

 vesica (vs, figs. 2, 6), and it serves to introduce the sperms into the 

 bursa copulatrix of the female. It is commonly armed with one to a 

 variety of spines, the cornuti (cn, figs. 2, 6), whose relative constancy 

 of size, shape, and number within each species is of great taxonomic 

 value for the separation of species. 



The harpes (fig. 1 and hp in figs. 5-6) are paired, lateral, clasping 

 organs attached to the vinculum and articulated with the anellus. 

 These symmetrical, flattened, roughly spoon-shaped structures are 

 subject to considerable modification of form among the various 

 species, thus furnishmg very good specific taxonomic characters. 

 The harpe can be roughly differentiated into three areas: a dorsal or 

 costal area, the costa (cs, fig. 1) ; a ventral area, the sacculus (sc, 

 fig. 1); and, an apical area, the cucullus (cu, fig. 1) or valvula. Nor- 

 mally, these are simply defined by areas of heavier sclerotization, 

 inward foldings, and the location of setae (ps, figs. 1, 5). Any one 

 of these major areas may be developed at the expense of the others. 

 Rarely, the costa is developed mto a free extended arm, the costal 

 arm or costal process (cp, fig. 1), forming a double harpe structure. 

 The sacculus is never developed into a clasper. However, a clasper 

 (cL, fig. 1) does occur rarely on the inner surface of the cucullus. 



The transtilla (tr, fig. 1) is reduced, broken in the middle, and 

 occurs as a pair of free, glabrous, well sclerotized arms suspended from 

 the inner costal angles of the harpes. These arms, which are some- 

 what variable within any one species, are not of much taxonomic value 

 in separating the species. 



