THE WESTERN CABBAGE ELEA-BEETLE. 
except in a few darker r individuals from northern Colorado, the 
normal color being almost uniformly cupreous or copper-colored. 
The species is also apt to be confused with PJt. aeneicollis Cr., but the 
latter may be readily distinguished, inasmuch as it is more convex, 
more shining, and distinctly larger. 
EGG. 
The egg is light yellow, glistening, of oval form, and about 1/50 
of an inch in length. 
In confinement eggs were deposited in cracks in the soil about 
the roots of the cruciferous plants on which the larva subsists and 
there is good reason to believe that this 
is the usual habit under field con- 
ditions. 
LARVA. 
The larva (fig. 2, a, b) is thread-like 
in appearance, uniformly white, except 
for the head sclerites, the legs, and a 
chitinized area on the caudal abdominal 
segment, which are pale chestnut brown. 
The mature larva is about 5 mm. in 
length and from 0.5 to 0.65 mm. in 
width, or approximately 10 times as 
long as wide. 
The larvae feed normally on the roots 
of cruciferous plants and remain con- 
cealed in the soil throughout their life. 
PUPA. 
On reaching maturity the larva selects 
a suitable place for transformation and 
then wriggles about until it has formed 
a compact, well-defined cell in the soil, 
in the vicinity of the roots on which it fed. After the cell is formed 
the larva shortens and in about two days changes to pupa. 
The pupa (fig. 2, c) is approximately of the same size as the adult 
and is en t- rely white. The arrangement of the antennae, legs, and 
wings is the same as that of the average halticine pupa. 3 
DISTRIBUTION. 
The range of the western cabbage flea-beetle, accorded by Horn 
and others, is from the Dakotas to Mexico and central and southern 
California. 
Fig. 2.— Western cabbage flea-beetle: a, 
Outline of larva, lateral view; b, head 
and thoracic segments of same, dorsal 
view; c, pupa. Enlarged. 
s Detailed descriptions of the immature stages are omitted from this paper 1 realise fresh material is not 
available and it is, moreover, desirable to compare all cf these stages with those of related species and 
illustrate the same. 
