: MEXICAN BEAN BEETLE IN THE SOUTHEAST. 3 
Tenn., where the insect was not known to occur until 1921, the same 
situation occurred in 1922, one year after the insect reached that 
region. (Figs. 1, 2.) By the fall of 1922 practically no beans 
were growing about Chattanooga. Serious damage also occurred 
about Atlanta and other points in northern Georgia, and in many 
sections of eastern Tennessee. 
DESCRIPTION. 
The Mexican bean beetle is a robust, hard-shelled insect of hemi- 
spherical form bearing eight black spots on each elytron or wing 
cover. (Fig. 3; Pl. Il, A.) Typical adults measure about one- 
fourth to five-sixteenths inch in length and one-fifth to one-fourth 
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Fic. 3.—Adults of the Mexican bean beetle, showing variations in size and marking. 
inch in width, and when fully mature are copper-colored. Newly 
emerged specimens are light lemon yellow. Males are distinguished 
from females by a notch in the posterior abdominal segment, this 
notch being absent in the females. Males average slightly smaller, 
but many are as large as females. 
The eggs are small, about one-twentieth of an inch long, orange- 
colored, and are laid in masses of from 40 to 60 on the under sides 
of the bean leaves. 
The larve, on hatching from the eggs, are orange-colored, and 
are covered with long branched spines. (Fig. 4; PL LAs) Phew, : 
Bow rapidly and become about one-third inch long and half as wide | 
efore pupation takes place. (PI. II, B.) 
The pupa is almost the size of the beetle, is yellow, and is attached 
to the leaf or object on which it pupates by the last larval skin, 
which is white and spiny and covers the posterior abdominal seg 
ments: “(Ph itl A, B.) | 
