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separated from others by having five inner spines above on the hind tibiæ, the third and fourth of which have the greatest interspace between them.

Life History. The life history of this species is not well known, as practically its entire existence is spent underground. All stages, from young to adult, appear the same, except in size. They feed upon the roots of plants.

Distribution. This species is more particularly confined to the central and southern parts of the State, though they probably also occur in the northern part, especially in the Sacramento Valley.

Food. The feeding habits of these peculiar insects are not well known. Some are carnivorous, while others are believed to feed upon decaying vegetable or animal matter. However, we do know that they are often responsible for considerable damage to potatoes before they are dug. The tubers are gnawed so as to be unfit for keeping or selling. Occasionally a large proportion of the crop may thus be injured, but this is more likely to happen only in small places.

Control. The most injury is done in fields placed under cultivation for the first time or lands left for some time to sod or pasture. Well cultivated fields seldom if ever suffer from the attacks of this pest. Clean cultivation around the fences so as to break up the breeding places will practically eliminate all possibilities of injury.

GRYLLIDE (Family).

CRICKETS.

The members of this family, like the Locustida, have long filiform antennæ, but the tarsi are three-jointed and the ovipositor is spearshaped. Many of the species are wingless. When the wings are present they are deflexed on the outer edge and fold closely to the sides and back. This is also a musical family. All species are injurious to vegetation.

The common field crickets are most abundant and familiar. They seldom do enough damage to deserve special treatment here. The tree crickets are almost arboreal in habits and do considerable damage to economic plants by making incisions in the smaller branches and stems into which the eggs are deposited.

THE SNOWY TREE-CRICKET.

Ecanthus niveus DeGeer.
(Fig. 24.)

General Appearance. The adult insects are slightly more than half an inch long and light yellow or greenish in color. The antennæ are very long and hair-like. There is one black dot on the face beneath each antenna. The females appear narrow, because the wings are

folded along the sides and over the backs, while in the males they are spread out flatly on the back. The black-tipped ovipositor also helps. to distinguish the female. The eggs are about one eighth of an inch long, slender, slightly curved and white. They are inserted in the stems of the host.

Life History. The eggs are placed singly in the canes or twigs in the autumn and remain dormant during the winter. The first warm spring days cause them to hatch and the young, wingless, green crickets begin feeding upon plant lice or other soft-bodied insects.

Throughout its entire life, from the time it leaves the egg until egg-laying commences in the fall the insect is working for the benefit of the farmer. By autumn all forms are mature and egg-laying begins, the adults disappearing soon afterwards.

Distribution. Throughout the entire State.

Food and Host Plants. The damage done by the snowy tree-cricket is due almost entirely to its method of puncturing the small stems and canes in egg-laying. It often happens that so many eggs

FIG. 24.-Left, eggs of Ecanthus sp. a, twig showing punctures; b, twig split open to show eggs; e, egg; d, cap of egg. Enlarged. (After Riley.)

Upper right, female of Ecanthus niveus DeGeer. Lower right, male of Ecanthus fasciatus Fitch. which greatly resembles male of snowy treecricket. (After Lugger.)

are placed in the canes as to cause considerable loss. Raspberries and blackberries receive the most injury, though young deciduous fruit nursery stock is also often severely injured.

The feeding habits of this species places it among the beneficial insects and partially offset the damage in depositing the eggs. The young and old alike feed upon soft-bodied insects, principally plant

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lize, and due to their ravenous appetites they are able to consume great numbers of other injurious pests.

Control. The method of eliminating subsequent broods and attacks consists in cutting out all canes showing the characteristic signs of having been punctured for egg-laying (Fig. 24a). It has been said by many reliable authorities that the good done by the snowy tree-cricket in destroying injurious plant lice and other soft-bodied insects more than recompenses the farmer for the harm done and that only in rare cases should the eggs be destroyed, even after the injured canes or branches have been removed.

PLATYPTERA (Order).

The members of this order have direct or incomplete metamorphosis, the larvæ and nymphs not varying greatly in structure from the adults. The wings, when present are two pairs, membraneous, delicate, equal or front wings slightly larger. There are two suborders, Corrodentia and Mallophaga. Only the family Termitida of the Corrodentia will be considered here.

TERMITIDE (Family).

TERMITES OR WHITE ANTS.

(Fig. 25.)

These insects, though commonly called white ants, are not ants at all, being more closely related to the lower groups of insects rather than to the true ants. Some entomologists have placed them in a single order Isoptera.

A
B

C

DE F

FIG. 25.-Termes lucifugus Rossi. A, adult worker; B, soldier; C, perfect winged insect; D, same insect after shedding the wings; E, young queen; F, old queen. (After Grassi and Sandias.)

The eyes of the termites are faceted or made up of many apparently individual eyes; antennæ 9-31 jointed; prothorax large and well developed; abdomen elongated with ten segments; wings long, slender, membraneous, equal and delicate. The habits are social, there being abortive female workers, soldiers, males and sexual females or queens.

THE COMMON TERMITE.

Termes lucifugus Rossi.

(Figs. 25, 26.)

General Appearance. The workers of this species are rather small, being shown as natural size in Fig. 26. They are transparently white in color, the contents of the alimentary canal giving a yellowish or

ESSIG FIG. 26. - Termes lucifugus Rossi, working on roots of nectarine tree. (Original.)

brownish cast. The head is darker yellow and mandibles brown. The soldier ants have large brown heads, comprising at least one third of their entire bodies. The queen ant is much larger than the other forms, while the males are small. It is claimed that there are no less than fifteen kinds of individuals in this species.

Life History. These termites usually live in dead or decaying wood but often work into the living and growing tissues. They make very extensive galleries through all parts and thus often destroying buildings, fences, etc., as well as fruit trees. The queen gives rise to all the young, which appear in great numbers, especially during the summer months. In the fall or autumn winged or migratory forms appear and often fly by thousands on dark days and towards evening. In habits and life history they greatly resemble true ants and bees.

Distribution. This species may be found in almost every section of the State.

Food Plants. As previously stated, these termites usually work upon dead or decaying wood, but then usually only in the presence of moisture. In the southern parts of the State these insects have often become destructive to fruit trees, working upon the roots underground and making galleries up the trunk. No doubt they usually begin to work in the decaying tissues but often continue into the healthy portions of the tree. Nectarines, peaches and apricots seem to suffer most, while citrus and other trees and plants are also attacked.

Control. Due to their secluded work the damage is usually done before their presence is known and too late to effect a remedy. However, if close observations are made in infested districts and their work discovered the colony may be almost entirely exterminated by the use of a liberal dose of carbon bisulfid applied in cotton or a sponge directly within their burrows or under the base of the tree.

[graphic]

THYSANOPTERA (Order).

THRIPS.

The numerous species of the minute fringed-winged insects, known as thrips, are placed in a single order as given above. These insects. though exceedingly small, may be readily observed by simply shaking almost any flower, especially the sunflowers and their allies, into the hand and observing the small yellowish or brownish slender individuals crawling out in the palm of the hand. They hop and fly very readily. The eggs are laid upon the outside, or within the tissues of the plant. In the latter case the female inserts the egg with her sharp ovipositor. The insects have direct or incomplete transformations, the larvæ greatly resembling the adults. The pupa of some species have a quiescent stage, thus differing from most insects having incomplete metamorphosis, in which this stage is very active, differing from the adults only by the small wing pads. Those species having a quiescent pupal stage are characterized by the larvæ going into the ground for pupation and remaining there during the winter, the adult insects emerging in the early spring. The mouth-parts are modified so that the insects chafe rather than bite, and due to their constant work and tremendous numbers are able to accomplish very disastrous results. They work principally upon the young buds and flowers, though they often do considerable damage to fruits and foliage.

In this State thrips are among the most serious pests, especially in the Sacramento and San Joaquin valleys, where thousands of dollars are spent each year in protecting the orchards.

The control measures vary somewhat and are given under each individual species. Several species have been known to be attacked by internal hymenopterous parasites, but the exact amount of this parasitism for the various species is not well known.

THE BEAN THRIPS.

Heliothrips fasciatus Pergande.
(Fig. 27.)

General Appearance. The adult insect is black with head and thorax dark brown; antennæ are whitish with tips dark; legs are black and yellow; front wings are blackish with white base; posterior wings uniformly yellow with dark fringes. The young stages are lighter in appearance than the adult.

Life History. According to Mr. H. M. Russell the insects hibernate in the adult stage only, under leaves, rubbish, etc. They begin to emerge about January and immediately begin egg-laying. The ergs are inserted in the leaves or tender stems. The young begin feeding soon after hatching. When ready to pupate the larvæ seek shelter under rubbish or in the ground, where the nymphal stage is completed and the adults emerge. There is an overlapping of broods so that

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