512 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 114 



It has been observed in numerous dissections that when the vesica of 

 a prepared specimen is extruded by forcing alcohol or water into it, 

 the relative location and direction of its cornuti may be considerably 

 altered. This may be caused not only by the general expansion of the 

 entire vesica but also by the unequal expansion of areas differing in 

 degree of sclerotization. Thus, the armature of the unexpanded 

 vesica of a specimen simply cleared in potassium hydroxide may pre- 

 sent a quite different appearance from that of a simdar specimen 

 whose vesica has been fully expanded by the application of fluid pres- 

 sure. Because of this, the location and direction of the cornuti should 

 be considered as variable or secondary characters in comparison to 

 their less variable or primary characters of number, size, and structure. 

 The drawings in this revision were made from alcoholic specimens in 

 which sufficient fluid pressure had been applied to the base of the 

 abdomen to cause the entire genital capsule to extrude. 



It has been pointed out by Busck (1931, p. 206) and others that the 

 males in some of the groups of Microlepidoptera possess deciduous 

 cornuti. These are loosely attached to the vesica of the penis which, 

 in many species, is extended through the entire length of the ductus 

 bursae and into the bursa copulatrix of the female during copulation. 

 When the vesica is withdrawn after insemination, these cornuti are 

 left with the spermatozoa in the bursa. Busck states that "these 

 deciduous spines are normally flattened, very sharply pointed, and 

 often nearly as long as the diameter of the female bursa." They are 

 to be distinguished from the fixed cornuti which are firmly attached to 

 the vesica and are withdrawn along with the penis after copulation. 



Since the armature of the vesica has been given considerable weight 

 in the present separation and characterization of the various species 

 of Acrolophidae, it has been necessary to make certain that the cornuti 

 are of the taxonomically reliable fixed type. All of the writer's studies 

 of genitaha in this family have indicated the presence of this fixed 

 type, a few dissections having shown only slight evidence of the possi- 

 ble occurrence of the deciduous type. Preparations of the vesicae of 

 both very fresh (probably virginal) and very worn (probably non- 

 virginal) specimens of any one species have invariably exhibited 

 essentially the same armature. In addition, this armature, whether 

 in the form of very large or very small cornuti, has always been found 

 to be quite firmly attached to the vesica, even after thorough clearing 

 in potassium hydroxide. Lastly, various degrees of increased sclero- 

 tization have been frequently observed in those areas of the vesica 

 receiving the bases of the cornuti. Minor variations of this armature 

 among specimens of any one species, as well as the occasional ap- 

 pearance of an additional cornutus or sclerotized structure in the ves- 

 ica, may be reasonably attributed to intraspecific variation. 



