10 OUR SHADE TREES AND THEIR INSECT DEFOLIATORS. 
together in each group (Fig. 1 e, magnified), and so firmly fastened to 
the leaf that they can only be detached with great care without break- 
ing the thin and brittle shell. The number of eggs in each group 
varies from four or five to twenty or more. Very rarely only three eggs 
are seen in one group, but we never found less than that number. The 
egg itself is oblong, oval, obtusely, but not abruptly, pointed at tip, 
of straw-yellow color, its surface being opake and beautifully and 
evenly reticulated, each mesh forming a regular hexagon, as shown, 
highly magnified, in Fig. 1 f. The form of the eggs is not quite con- 
stant, 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 stiffer than in the full-grown larva. With each 
consecutive molt the yellow color becomes more marked, the black markings of less 
extent and of less intense color, and the hairs much 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 transversal dorsal markings, 
usually 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 nave 
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 opake, but those 
of the under side shining. The black markings are polished, piliferous, and raised 
above the remaining portions of the body. 
The larve 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 undergo 
four molts, respectively observed at Washington on July 15 (at hatch- 
ing) 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 (Fig. 1 j) is of a brighter color than the larva, oval in shape, 
and strongly convex dorsally. Itis 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 6-10 days. 
The perfect beetle (Fig. 1c, natural size; k magnified) resembles somewhat in ap- 
pearance the well known striped cucumber-beetle (Diabrotica vittata), but is at once 
