YUCCA MOTH AND YUCCA POLLINATION. 147 
spots, one above the other. When there are more than 
five spots, the additional spots are ranged around the pos- 
terior border. These spots are sometimes so small as to be 
confined to a single scale. 
PRODOXUS MARGINATUS Riley. 
[Pl. 43, Fig. 2.] 
This species was described in 1880 (Proc. A. A. A. 5S. 
Vol. XXIX.) from specimens collected by Mr. H. K. Mor- 
rison in Kern Co., Calif. I have since been able, through 
Mr. Koebele’s collecting in 1886, to rear it from the peti- 
oles and basal portions of the pods of Yucca whipplet 
obtained in Los Angeles Co., Calif., in the flowers of 
which it is also frequently met with from the end of April 
to the end of June. Its habits, so far as they have been 
observed, are quite similar to those of decipiens, the larve 
remaining within the petioles nearly a year, transforming 
and issuing during the ensuing month of April. No especial 
observations have been made on the method of oviposition 
and the egg has not yet been obtained. 
Larva. — Average length 8-4 mm. General color pale bluish-green. 
Head honey-yellow, marked each side of the clypeus with some more or 
less distinct but irregular dusky patches. The cervical plate con- 
colorous with the body, but marked in front and behind with two faintly 
dusky patches, otherwise agreeing precisely with P. decipiens. 
Curysal{s. — Except in the smaller size and less prominent spines and 
sculpturing, agreeing exactly with that of decipiens. This is especially 
true of the male chrysalis. The frontal tubercle in the female, besides 
being smaller, lacks the sharp lateral caring and has on the sides a shal- 
low longitudinal channel or depression. The dorsal tubercles on the 
eighth abdominal joint are also transversely ovoid instead of being per- 
fectly cylindrical at the base. 
ImaGo (Pl. 43, Fig. 2).—Expanse 8-10 mm. Color white, the clothing 
of body very sparse, especially on the abdomen, and showing more or 
less distinctly the integument which is dark brown often with an geneous 
tinge. Antenne bare towards tip and yellowish. Primaries ( Fig. 2, pr) 
satiny -white with a terminal black band of varying width; under surface 
fuscous, almost black on costal and posterior borders; fringes white. 
Secondaries white with a broad costal and apical fuscous shade; under 
surface concolorous; fringes white. Apical abdominal joint of 9 black- 
ish, slender, very obliquely truncate above, the tip blunt-pointed (Fig. 2, 
a). Ovipositor short and stout; the horny terminal joint gradually 
narrowed to the pointed tip, the upper edge very finely and acutely 
serrulate (Fig. 2, ¢jo). Claspers of (Fig. 2, c) not dentate, their 
form much concealed by scales, the large arms broad and of nearly 
uniform width; large upper basal piece obtusely angulated in the middle. 
