53 
The writer finally decided on a sort of compromise, using in a generic 
sense such terms as have already been created and which could be correctly 
applied to any given group, and lumping several groups under the one 
genus Graphiphora where no term was available. 
The species contained in this section appear to be rather primitive and 
possibly the remnants of an old insect fauna which was more or less common 
to both the Palaearctic and Nearactic regions, and in which the specific 
differences of the male genitalia were very marked. It might be deduced 
from this that the species comprising genera such as Euxoa and Agrotis 
which show marked similarity of genitalic structure are more recent and 
that in such cases the genitalia are of better generic than of specific value. 
Though inclined to think that such may actually be the case, the writer 
is not yet prepared to follow the matter to its logical conclusion and raise 
each group of Graphiphora to generic rank. 
Diarsia Hbn. 
1822, Verz. bek. Schmett. 222 (type, dahlii Hbn.). 
Eyes naked. Palpi upturned, with slightly porrected third joint; 
second joint fringed with rather rough hair and scales, terminating apically 
in a more or less evident triangular tuft; third joint rather long and smooth- 
scaled. Front smooth. Male antemne ciliate or weakly fasciculate. 
Tibiae all spined; fore tibia somewhat longer than first tarsal joint, smooth- 
scaled, with outer fringe of hair and only a single apical spine (occasionally 
a preapical one also) on outer side; a complete row of weak spines on 
inner side. Mid tarsi without fourth row of spines. Thoracic vestiture 
slightly roughened, composed of mixed single and bifid or trifid hairs, with- 
out noticeable tufting. 
Figure 32. Male genitalia of Diarsia cynica Sm. 
Male Genitalia. Clasper with the ventral margin strongly bulging 
centrally; corona present and supplemented by rows or tufts of spine- 
like hair; harpe of variable shape, at right angles to sacculus on a foot-like 
base; ampulla present, a narrow ridge of chitin between base of clasper 
and base of harpe, parallel to costa. Clavus absent. Uncus typically 
narrow and strap-shaped, at times with very broad truncate apex. Juxta 
strong with medio-apical margin typically strongly pointed. Vesica vari- 
ably armed with chitinous plates, single strong cornuti or bundles of small 
cornuti. 
