1900. ] GROTE—THE DESCENT OF THE PIERIDS. 2 
Or 
Gen. Zachyris Wallace, 1867. 
Type: ©. nero. 
Tachyris nero. 
In the shape of the more pointed primary wings differing from 
Pieris and Huphina, the neuration agrees generally and the special- 
ization seems to even exceed the latter. Radius four-branched ; 
Rr and #2 nearer together than in Auphina; apical fork even 
shorter. Cell closed; J/1 has ascended radius for about one- 
fourth of the distance from cell to margin; cross-vein between J/2 
and radius concave ; a slight mesial backward spur. Hind wings 
with humeral spur turning sharply outwardly. 
There are apparently four groups in this genus as established by 
Wallace, but I have only examined the type as given by Mr. Scud- 
der (Hist. Sketch, 274). 
Gen. Hebomoia Hiibner, 1816. 
by pe ci ils glaucippe. 
HHebomoia glaucippe. 
Agrees with Zachyris, but much more generalized, and there is a 
wide gap in the continuity which may be bridged over by forms to 
which I have not access. 
Radius four-branched ; Ar and #2 approached, but #2 well 
removed from cross-vein. Cells closed; 4/1 has not ascended 
the radius, as in the entire preceding series, but springs from cross- 
vein close to upper angle of discal cell. Traces of the base of 
media as in all generalized forms ; two parallel creases can be made 
out, the upper joining to a slight backward spur at the origin of J72, 
the lower from a similar point at the centre between J/2 and 
M3. First anal vein a very strong scar; this vein is only devel- 
oped, however, incompletely in generalized forms. A strong fork 
to second anal at base. Hind wings with pointed humeral spur 
turned sharply outwards. Traces of a splitting of S at base, thus of 
a subcostal cell. Wings with transparent but strong veins. 
This is the most generalized form which I can refer to the prob- 
able direct line of Pzeris,; it is a long way behind, from the fact 
that 4/1 lags upon the cross-vein. ‘The line of Prerzs'seems to 
have connected with the Aforta line, which we now take up, and 
through forms like Zhesty/is, which may almost belong to either. 
