144 MISSOURI BOTANICAL GARDEN. 
Larva (Pl. 41, Fig. 2, a).— Length when full-grown, 14 mm. 
Somewhat more cylindrical than that of yuccasella, the general color 
being bluish-green tinted with a rosaceous hue; otherwise undistin- 
guishable from those of the other two species, 
Curysavis (Pl. 41, Fig. 2, 6,c).—Insize, general shape and arrange- 
ment of the spines similar to that of yuccasella, but readily distinguished 
by the wing-sheaths in both sexes reaching only to the sixth abdominal 
joint and the posterior legs to the seventh, whereas in yuccasella the 
former reach to the eighth and the latter to about the middle of the 
ninth. The medio-dorsal spines are also longer, more prong-like and less 
spatulate, while the capitate spine is perhaps less prominent. The dif- 
ference is more particularly noticeable in the greater length and promi- 
nence of the two spines on the second abdominal joint. The anal joint 
in the male is narrower and comparatively longer, and the two terminal 
teeth much shorter than in the female, also not so well defined as in 
yuccasella, The anal segment in the female is broader and stouter than 
Ma yuccasella, with the teeth shorter, stouter and further apart. (c, d, e, 
> 9) hs) 
ImaGo (Pl. 41, Fig. 1, @).— Expanse ?, 15-20 mm.; < 16-18 mm. 
Body flattened, piceous. Wings smoky-gray; the scales sparse and as 
easily lost on the upper surface, especially of primaries, as in the Sesiidae, 
so that none butthose carefully killed soon after issuing fromthe chrysalis 
show the wings well covered. In such specimens the general color is 
cinereous, the primaries but slightly darker than secondaries, the scales 
being narrow and elongate, mostly gray, but with an admixture of black 
ones. The exposed membrane of the wing is fuliginous except a nar- 
row discal space and more or less of the costal region which remain 
sordid white. Fringes paler but sparse and easily lost except at anal 
angle of hind wings, where they persist. Veins black and strong. Body 
but sparsely clothed in freshest specimens and soon becoming bare 
except at neck; highly polished and minutely punctate, and in some 
specimens with metallic tendency. Head (Fig. 1, 6) with the hair pale 
ferruginous; eyes brown, naked; labial palpi bownish-black with sparse 
white scales; maxillary tentacles stout and brown, shorter than tongue; 
max. palpi nearly as long as tentacle, basal joint stout, rounded, joints 2 
and 8 short, sub-equal in length, joint 4 very long, terminal joint with 
two spines at tip; tongue very stout, long and ferruginous; antennae 
black. Thorax with two singular transverse-ovoid translucent and 
somewhat opalescent spots recalling the so-called cenchri of Tenth- 
redinids; legs stout and dark, the hind tibiae and tarsi pale ferruginous. 
Abdomen separated from thorax dorsally by a broad and deep suture 
which is pale rufous by contrast with the general piceous color; anal 
joint (Pl. 42, Fig. 1, c, d) in Q rufous, with darker shade at base, 
the sides compressed from above and expanded into a broad and angu- 
late wing, the borders of which are thickened and stiffened and con- 
verge to a rather sharp tip which is, however, obliquely truncate from 
the side; ovipositor issuing generally at right angles and with the same 
parts as in yuccasella but all stouter and shorter (e,f). In the % the 
dorsal fulvous suture or pit between thorax and abdomen is more pro- 
found and concave, the abdomen is less flattened and the claspers are 
brown, very stout, one-half as long as the abdomen, the basal part 
broad and leaf-like, the terminal part abruptly curved upward, dilated 
into a decurved triangular tip, and the prong quite long, slightly curved 
and denticulate at tip (a, 0). 
Described from 28 22, 10 do, from the fruit of Yucca brevi- 
folia. 
