THE IMPORTED ELM LEAF-BEETLE. i 
color, its surface being opaque and beautifully and evenly reticulated, 
each mesh forming a regular hexagon, as shown, highly magnified, in 
Fig. If. The form of the eggs is not quite constant, some of them, 
especially those in the middle of a large group, being much narrower 
than others. The duration of the egg state is about one week. 
The general shape of the larva is very elongate, almost cylindrical, and distinctly 
tapering posteriorly in the early stages, but less convex and of nearly equal width 
when mature. The general color of the young larva is yellowish-black, with the black 
markings comparatively larger and more conspicuous, and with the hairs arising from 
these markings much longer and stifferthan in the full-grown larva. With each con- 
secutive molt the yellow color becomes more marked, the black markings of Less 
extent and of less intense color, and the hairs mnch shorter, sparser, and lighter in 
color. A nearly full-grown larva is represented in Fig. 1 g, and in this the yellow 
color occupies a wide dorsal stripe and a lateral stripe each side. The head (except- 
ing the mouth-parts and anterior margin of the front), the legs (excepting a ring 
around the trochanters), and the posterior portion of the anal segment are always 
black. The first thoracic segment has two large black spots on the disk, of varying 
extent, and often confluent. The following segments (excepting the anal segment) 
are dorsally divided by a shallow transverse impression into two halves, and the black 
markings on these halves are arranged as follows : two transverse dorsal markings, 
usualty confluent, as shown in our figure ; two round and sublateral spots ; the tips of 
the lateral tubercles are also black. The abdominal joints of the ventral surface have 
each a transverse medial mark, and two round sublateral spots of black color. Stig- 
mata visible as small umbilicate spots between outer sublateral series of dorsal mark- 
ings and lateral tubercles. The'yellow parts of the upper side are opaque, but those 
of the under side shining. The black markings are polished, piliferous, and raised 
above the remaining portions of the body. 
The larvae are destructive to the foliage from the month of May until 
August. They have about two weeks of active life between the egg 
and pupa states. During this time they prey upon the leaves, which 
become skeletonized, leaving the venation and commonly a certain 
portion of the flesh of the leaf, which becomes rust-brown. They un- 
dergo four molts, respectively observed at Washington on July 15 (at 
hatching), 20, 23, and 29 (pupation). When full-grown they descend to 
the ground and change to pupa under whatever shelter is near to the 
base of the tree. 
The pupa is of brighter color than the larva, oval in shape, and 
strongly convex dorsally. It is sparsely covered with moderately long 
but very conspicuous black bristles, irregularly arranged on head and 
thorax, but in a transverse row on each following segment. The pupa 
state lasts about from (j-10 days. 
The perfect beetle (Fig. 1 o, natural size; /,-, magnified | resembles somewhat in ap- 
pearance the well-known striped Cucumber-beetle (Diabrotiot rithita^, hut is at ones 
distinguished by the elytra not being striate punctate, but simply rugose, the sculpt- 
ure under high magnifying being represented in Fig. 1 /. The color of the upper side 
is pale yellow or yellowish-brown, with the following parts black : on the head a 
frontal (often wanting) and a vertical spot: three spots on the thorax : on the elytra 
a narrow stripe along the suture, a short, often indistinct scutellar stria each side. 
and a wider humeraj stripe not reaching the tip. Under side black, pro and meso- 
steruum and legs yellow, femora with a black apical spot. Upper and under side 
covered with very tine, short, silky hairs. In newly-hatched individuals the black 
markings have a greenish tint; the humeral stripe varies in extent. 
