15 
are rapidly increasing, although it continues to live by preference on 
weeds and wild plants. The crops most injured are beets, spinach, 
and saltbush; and natural food plants are chickweed and lambsquar- 
ters. The leaves of these plants are riddled with holes, chiefly the 
work of the larvae, but also of the beetles, and gardeners complain 
that spinach may be so badly worm-eaten that it is impossible to offer 
it for sale. Considerable injury to beets was observed by the writer 
in 1900, and during 1902 and 1903 the insect has been the most con- 
spicuous species on sugar beet in and near the District of Columbia. 
The larvae, as well as beetles, drop quickly upon being disturbed, 
and as the former are inconspicuous in appearance, and the latter feign 
death, the miscreants are apt 
to elude recognition, the 
earty injury produced being 
frequently ascribed to cut- 
worms and the later damage 
to other insects. Frequently 
from 15 to 20 larvae live 
on a single leaf. They feed 
mostly on the under surface. 
The beetle (fig. 7, a) is shin- 
ing black, sometimes with a 
greenish or bluish luster. 
The pro thorax and abdomen 
are red or reddish yellow, 
and the legs and antennae pale 
yellowish. It measures less 
than one-fourth of an inch. 
The buff or orange eggs (5, W) 
are deposited in masses. The 
mature larva (c) as it occurs 
on sugar beet is dull leaden gray, with darker head and still darker 
brown mouth parts, but on red and purple beets it takes on the color 
of the plant attacked. This is a native species and of exceptionally 
wide distribution, its habitat extending from New England to Mon- 
tana, and from British America to Florida and Texas. It is one of our 
earliest spring visitors, appearing in the first warm days of March in 
the Atlantic States, and continuing abroad some years through Novem- 
ber. Two generations occur in the District of Columbia, the first 
usually produced on chickweed, and later ones on beets, spinach, and 
other plants. It is a prolific insect, as many as 180 eggs having been 
observed to be deposited by a single female." 
bb b c 
Fig. 1 .—Disonycha xantliomelxna: a, beetle; 5, egg mass, 
showing mode of escape of larva at right; bb, sculpture 
of egg; c, full-grown larva; d, pupa; e, newly hatched 
larva; /, abdominal segment of same — a, c, d, five 
times natural size; b, e, more enlarged; bb,f, still more 
enlarged (author's illustration, Division of Ento- 
mology). 
a A more complete account of this flea- beetle is given in BuL 19, n. s., pp. 80-85. 
