138 
Psyche 
[j une-August 
them in localities about New York where vittata was known to 
occur, but without success. This appears significant, but the 
possible effect of climatic difference on fertility must be con- 
sidered. Marchand concluded that nais, vittata and phalerata 
were distinct species; he reared several broods of nais and 
phalerata which always bred true. His attempt to cross these 
moths was unsuccessful as would be expected from the genitalic 
differences, which he notes. 
It is not necessary to assume that interbreeding must occur 
to explain occasional extraordinary resemblances between these 
forms. Variability is inherent in living organisms, and since the 
characters which vary in these moths are the same in all, any 
departure of a form from its normal mean makes it approaach 
one of the other forms. Also, in closely related forms apparently 
recently differentiated the occurrence of atavism may explain 
some of the intergrading individuals. 
There is nothing in the literature on the genitalia of Apan- 
tesis with the exception of a brief paper by Dyar in which he 
figures the claspers and tegumen of nais, vittata, and phalerata. 
Dyar concluded that phalerata was a good species, but later 
placed it as a variety of vittata in his catalog. 
The species of Apantesis as a whole show a wide range in 
the form of the male abdominal appendages. The moths of the 
nais group differ in common from the other species which I have 
examined. The sedoeagus in other species than those of the 
nais group is evenly and moderately chitinized thruout, except 
for occasional thickening near the orifice, and is unarmed. In 
the nais group this organ has a part of the circumference of the 
distal half thickened and heavily chitinized, and armed with one 
or more stout spines. I find no name in the literature which 
seems to apply to this localized area of thickened chitin in the 
sedoeagus, and will refer to it as the callum (“thickened skin”). 
In this thickening and armature this group resembles other Arc- 
tiidse, in some of which the sedoeagal armature is highly developed. 
The claspers are inwardly concave, roughly quadrilateral in 
shape, with an arm arising from the upper edge and projecting 
inwardly toward that of the opposite clasp. The distal portion 
of the clasper is composed of two distinct layers of chitin; the 
