Bulletin 151, Truck and Garden Insects


bores into the pods and feeds on the interior. Control meas-
ures are the same as those used against this insect on toma-
toes, page 189.
 COTTON SQUARE-BORER (Uranotes mellinus)
 This butterfly, called the gray hair-streak," deposits eggs
 on okra. The larvae, a green caterpillar, eats the leaves and
 bores into the buds. The purplish butterfly has a small narrow
 tail-like appendage projecting from its hind wings. It is this
 appendage that suggests the name of "hair-streak." The but-
 terfly measures about 21/ inches across the wings. Besides
 attacking cotton, where it mines into the squares, the caterpil-
 lar attacks loquats, where it mines into the blossom buds. (See
 An. Rep. Fla. Agr. Exp. Sta., 1913, page ixx.)

 ONIONS
 ONION THRIPS (Thrips tabaci, Lind)
 These thrips (fig. 98) are responsible for the blanching
 and withering of the tips of onion leaves. They are always
 present in onion fields in Florida, working thruout the year,
 except during the cold-
 est days of winter.
 Like other thrips, they
 are always more abun-
 dant in continued dry
 weather, and compar-
 atively scarce after a
 prolonged rainy pe-
 riod. They are deli-
 cate insects, about
 1/25 of an inch long,
 and are knocked off
 the plants and killed
 by heavy rains.
 Thrips belong to the
 sucking class of in-
 i sects. Their punctures
FIG. 98.-Onion thrips (Thrips tabaci). Greatly are not deep but are
 magnified. (Fla. Agr. Exp. Sta. Bul. 46.)
 very numerous so
that the plant tissue, when the fresh wound is examined, has
the appearance of having been rasped. Later, the tip of the
leaf whitens and shrivels. This continuous killing of leaves
greatly interferes with the growth of the onions, and control