ADELPHA. 295 
oa 
We should have been glad to have continued the name Heterochroa proposed by 
Boisduval, and so carefully defined by Westwood; but that name has previously 
been used for a genus of Caryophyllacee. We therefore follow Mr. Kirby in falling 
back upon Hiibner’s title Adelpha. 
In all species of Adelpha we have examined the primaries have a rudimentary 
interno-median nervure near the base of the median on the underside; this is directed 
rather outwards and not across towards the submedian. We find this rudimentary 
nervure present in “ Limenitis” lorquint and in L. camilla, but in Limenitis populi we 
do not trace its existence. 
There is but little variation in the neuration of the primaries in Adelpha; the sub- 
costal of all emits two branches before the end of the cell; the upper discocellular in 
some species, such as A. iphicla, is evanescent; in others it is very short (A. celerio, 
A. erotia, A. fessonia, A. melanthe, &c.); the middle discocellular is usually rounded, 
but in A. fessonia it is almost straight, and placed obliquely across the wing. The 
lower discocellular is always present in an atrophied state; it usually starts from the 
junction of the middle discocellular and lower radial, and passes in a simple curve to 
the origin of the second median branch. In A. fessonia it joins the median on the 
proximal side of the second branch, and in A. bredowi on the distal side of the same 
point. The neuration of Limenitis camilla is practically the same as that of Adelpha 
iphicla, except that in the Jatter the distance from the base of the cell to the origin of 
the upper discocellular is greater than the distance from the same point to the origin 
of the second median branch; in the former the reverse is the case. Limenitis lorquint 
agrees with J. camilla in this respect, so does L. populi. But the transition between 
these species is completely shown in the various forms of Adelpha. The front legs of 
the male in this genus vary but little; the coxa is stout, > 4 femur+trochanter; the 
tibia< femur ; tarsus (single-jointed)=$ femur. In A. bredowi the tibia is short, the 
tarsus being equal to it ; in A. sophar the tibia is as long as the femur, and the tarsus 
short. The legs of Limenitis camilla and L. lorquini are very much like those of 
Adelpha ; those of L. popwlt have a much thicker tarsus. The eyes are hairy in front, 
except in A. bredowi, which agrees in this respect with L. lorquini, the other North- 
American Limenitis, and with LZ. camilla and L. populi. The antenne have from 49 
joints in A. bredowi to 37 in A. leucophthalma, with nearly every intermediate number ; 12 
or 14 joints form a slight club. Limenitis popult has the smaller number, L. bredowi the 
larger. The terminal joint of the palpi is very short, the middle joint of nearly uniform 
width throughout. The male secondary sexual organs are more uniform in structure 
than usual; the tegumen has a rather long slightly depressed central spine, beneath 
which is a single projecting spine in the cavity of the structure; the harpagunes in 
most species have a lobe starting from the middle of the ventral edge, and directed 
upwards and slightly serrated on the inner edge; they have a longitudinal fold along 
the middle of nearly their whole length, and they usually end in a blunt point, which 
