YUCCA MOTH AND YUCCA POLLINATION. 137 
THE SPECIES OF PRONUBA. 
GENERIC CHARACTERS OF PRONUBA. 
IMaGo. — Primaries (P1. 34, Fig. 3, h) elliptical, the apex subacuminate ; 
disc closed, though somewhat indistinctly between marginal veins 5-8; 
12-veined, exclusive of sub-median (1, a); costal vein stout, connected 
with sub-costal near base, and not extending beyond middle of wing; 
the sub-costal vein sends, from about one-fourth its length from base, a 
branch which reaches costa where the latter commences to round off; it 
also sends, from about the middle of the wing, a branch through the discal 
space, forming an accessory discal cell, and sometimes considerably 
passing the disc, and forking outside, so as to form marginal veins 7 and 
8, though more often forking just at the transverse discal vein; a feeble, 
disco-longitudinal veinlet starts independently near the base, forks near 
the middle, and forms a second accessory discal cell; sub-median vein 
distinct only near the margin, and indicated by an opaque line along the 
basal half of the fold; internal vein feeble and bifid at basal third. 
Secondaries (Pl. 34, Fig. 3, ¢) broad, subacuminate at tip; shoulder 
slightly produced and armed in the ' with a long spine, and in both 
sexes with a tuft of long scales; 8-veined, exclusive of sub-median (1, 
a), which is distinct; disc entire; costal vein extending three-fourths 
of the length of wing; an independent, feeble, disco-longitudinal veinlet, 
forking about the middle of the wing, the upper branch sometimes con- 
siderably passing the disc, and then forking into marginal veins 5 and 
6, but more often forking at transverse vein; internal vein feeble and 
simple. Head (PI. 34, Fig. 3, a, 9), free, sparsely haired; epicranium 
flattened or depressed; ocelli obsolete; clypeus large; eyes round and 
salient; antenn filiform and simple in both sexes, nearly one-half as 
long as front wing, the basal joint long, bulbous, and twice as stout as 
the others; maxillary palpi (Fig. 3,0) very long, 5-jointed, the basal joint 
in the Q produced into a long, stout, cylindrical, prehensile tentacle, armed 
with spines springing from flattened tubercles (c); this joint in the ja 
mere blunt-pointed tubercle (d), the other joints almost smooth; 2d, short, 
stout, and directed backward; 3rd, more slender, and as long again as 
2nd; 4th, thrice as long as 8rd; 5th, as long as 2nd, slender and subfu- 
siform; the tip generally notched; labial palpi (g) moderately covered 
with hair-like scales, reaching nearly to base of antennx; 3-jointed; basal 
joint curved and stout; 2nd, half as long and straight; 3rd, short and 
fusiform; tongue long and smooth. Legs with the front femora and tibize 
short, the hind femora and tibiw long and stout; the usual single 
spur on the front, a pair on the middle, and two pairs on the hind tibiz. 
Abdomen Q with the anal joint long, horny, nearly bare; the ovipositor 
long, extensile, formed of two rods, the membranous covering of which 
is imbricato-granulate at base, the tip horny, serrate, and with a serrulate 
dorsal wing; ' shorter, blunt, and slightly swollen at tip; the genital 
hooks large, sub-spatulate, symmetrical; the upper edge entire and 
