THE ROUGH-HEADED CORN STALK-BEETLE 9 
LARVA 
DESCRIPTION 
The full-grown larva of Huetheola rugiceps (fig. 2.) is a robust, 
thick-bodied grub, with an approximate length of 32 millimeters 
(14 inches) and an average thickness of about 6 millimeters. It is 
nearly pure white, deepening posteriorly to a dark gray or brownish 
tint, due to the dark color of the vis- 
cera appearing through the trans- 
parent cuticle; the legs are yellowish 
amber; the spiracles orange; the head 
shield a distinctly reddish hue, closely 
approximating a bright shade of In- 
dian red. In alcoholic specimens these 
colors are invariably much obscured. 
The most distinctive morphological 
features of the larve are found in the 
head shield and the last ventral seg- 
ment. The head shield (Pl. IIT, 4) 3 
is distinctly, even coarsely punctate, rire, 2.—Full-grown latva of Euethe- 
ae 
the punctures being especially coarse pla susiceps. | Note relative a 
and dense on the portion immediately — Walton) 
above the clypeus. 
The last ventral segment of the larva (PI. III, D) bears a some- 
what irregular, median, double row of modified bristles, each having 
the appearance of a denticle or minute spine. In the possession of 
this feature the larva of Huetheola rugiceps is unique, so far as the 
writers are aware, among the. Dynastini and agrees with the larve 
of the genera Phyllophaga and Anomala, though i in these the corre- 
: sponding character is much more regular and 
i das, clearly ‘defined’ than in Euetheola ibe We 
D-G). Yn all other respects it resembles the 
type of larva normal to the Dynastini. 
METHODS OF COLLECTING AND REARING 
Owing to the pugnacious habits of the larve 
it is best to place each in a separate receptacle 
Fig. 3.—Young larva of. When collecting, also to place a little vegetable 
peel ieee. ~~ mold or fine soil in the box to prevent the larva 
hatehing. Note rela- > 2 
Bee ere ote Bela: from rolling about and being injured. 
trunk, in comparison Attempts were made to rear the larve in 
by Wk. Walton)‘ flowerpot cages, similar to those used to confine 
the beetles, but the results were disappointing. 
The failures were perhaps due, in part, to the fact that suitable food 
was not supplied the young larvee when the cages were started, as 
the food requirements of the young larvee were then very imperfectly 
known; possibly, also, to inability to protect the larve against cer- 
tain of their enemies. Ants frequently invaded the cages, and, as 
they are known to attack and kill the larve, were doubtless respon- 
ible in some measure for the unsatisfactory results obtained. The 
94051°—24-—2 
