1900. ] GROTE—-THE DESCENT OF THE PIERIDS. 15 
A trace of this tendency is, however, visible in the Skipper 
Angiades sylvanus. Here, on the fore wings, this vein, 1/2, still 
keeping central, has succeeded in sustaining its connection with 
the cubitus by a true vein ; that is, the lower part of the cross-vein 
between d/2 and 4/3 has retained its functional character, while 
the upper portion, between J/2 and J/1, has yielded to disin- 
tegration and become a scar. Hence J/2 is still fed from the 
cubitus. On the hind wings vein J/2 has failed to retain the 
connection, the source of blood supply has given out with the dis- 
integration of the entire cross-vein, and, in consequence, this mid- 
dle branch of the media has almost entirely vanished from the 
surface of the wing. 
Of the genera of the Dismorphianz, Mr. Scudder gives the type 
of Dismorphia : lata ; of Leptalis : astynome. Additional genera are 
given by Dr. Dixey in a footnote, Zrans. Ent. Soc. London, 
1896, p. 65. Mr. W. F. Kirby kindly informs that the types of 
these are: of Pseudopieris: nehemia ; of Enantia: melite; of Mos- 
choneura: methymna. Of these types I have been unable to pro- 
cure specimens of the first and last for study. 
Gen. Leftafis Dalman, 1823. 
Type: L. astynome. 
Leptalis astynome. 
Radius five-branched, all the branches arising beyond the cell ; 
#1 fusing above with subcostal vein. Cell closed, long and nar- 
row ; cross-vein deeply concave, somewhat weakened. First median 
branchlet arising at junction of cross-vein with radius; J/2 cubital. 
No trace of fork to second anal. Hind wings with hardly abbrevi- 
ate somewhat pointed costal, curving toward base of wing; no 
trace of subcostal cell. First median branchlet has left cross-vein 
and arises from radius at about one-third of the length from cross- 
vein to external margin. Cell closed ; J/2 cubital. 
This genus is, perhaps, less specialized than Pseudopieris, in 
which the discal cell is superiorly retreated, leaving //1 to spring 
from radius beyond it. It is more specialized than xantia (to 
which it stands nearer) and Acmepieron, because in these the first 
median branchlet still remains on the cross-vein. 
Leptalis melita. 
I describe this since the species has become well known, owing 
to its having been cited by Fritz Miiller as an example of the primi- 
