{June 1884. BULLETIN BROOKLYN ENTOM. SOC. VOL. VIL. 21 
and curve backwards till they run nearly parallel with the margin of the 
wing. Ina few instances, I have found the frenula slightly bulbed at 
the extremity. 
The Zegs are somewhat lengthened, robust and powerful. The cove 
are rather stouter and longer than those of Agvrofs being one-third as 
broad as long. The /¢rochanters offer no observed differences. The 
femora are rather long and slender, and somewhat flattened, laterally. 
They are generally, if not always. covered within with long hair, which 
on the fore and middle legs becomes exaggerated. This is not a character 
special however to Cafocula, but seems to be a tendency of the lower 
Noctuide. On the femur of the fore leg is an organ which seems heretofore 
to have escaped the observation of students of structural anatomy. 
I have found no mention made of it in the works of Guenee, Lederer, 
Herrich-Schaeffer, Burmeister or others, It is a special piece of arma— 
ture, situated on the femur of the fore legs of the males only, near its 
juncture with the tibia, at the middle of the upper or frontal portion, 
and consists of a chitinized spine set in a socket. It is corneous, cylin- 
drical, pointed at the apex, swollen in the middle. and narrow, almost 
pointed, at the base. It is ordinarily about one-half the diameter of the 
femur in length, and may be known as the gonyodon, (gonu, knee, and 
odous, tooth), or femoral spur. It is ordinarily hidden in the vestiture of 
the femur. Upon search I found it on the fore femora of the males of 
all the Ca/oca/e. It is also present in a number of the lower genera of the 
Noctuidae, though wanting, so far as I have observed, in nearly allied 
genera such as Synedu, Vpsia (Homoptera), and the Deltords. In Euclidea 
it takes a peculiarly curved form. In Paradlelia bistriaria, and Agnomo- 
nia amilis, | have found in the place of one, two of these gonyodons 
present. This organ is subject in the Cu/ocale to considerable variation 
in form, as may be seen from the figures of the plate. What may be the 
use of it I will not venture to guess. 
The #26zae are comparatively slender, though not lengthened. The 
Sore tibize present marked differences in armature, which seem to have 
heretofore escaped the attention of our systematists, and which divide 
the genus into two divisions of subgeneric standing; the one Catocala 
proper, having the fore tibiz unarmed, the other, which I will call Casa- 
bapia (kata, beneath, and dapios, dyed), having the fore tibia always, 
and generally very heavily spinulated. 
