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the insect has reached maturity, it assumes different shades of color—first, greenish brown; half grown, reddish brown, and at maturity, dark brown.

It is doubtful if there are more than one brood in each year. The first brood is hatched, in Sacramento, about the first of May, but do not attempt to leave from under the scale until the twelfth, yet it is very common to find thefemales of this species depositing their eggs late in September, but whether they are of the spring brood I am not prepared to say.

In relation to the length of time the lecaniums are capable of moving from one place to another, Mons. V. Signoret writes: "Before pregnancy they have the power to move, if necessary."

THE RED SCALE. (CAL.)

(Aspidiotus aurentii—Maskell.) Synonym, Aspidiotus citrii— Comstock. Order, Hemiptera; sub - order, ITomoptera; family, Coccidce.

[A circular reddish scale insect, infesting the citrus trees, and has been found on grape-vines and the foliage of walnut trees.]

The red scale infests some of the citrus groves of Southern California, and orange trees in Sacramento and Marysville. It has also been found on grape-vines and on the foliage of walnut trees, but I do not think that any damage will be done to these plants by this pest. As the walnut sheds its foliage annually, the insects are likely to be destroyed; and those which I have examined on the grape-vines in the month of September, and which appeared to be in a healthy condition, were dead and shrunken when I examined the vines in the month of February following.

It is generally conceded that this species is an importation from Australia.

Natural History. — Female scale, nearly transparent, circular, of a lightgrayish color, and measures from one line to one and one-quarter lines in diameter; exuviae or cast skin in center, yellowish; second larval skin easily distinguished.

Male scale, a little darker in color and smaller than the female scale; form, elongated; exuviae nearest the anterior end.

Eggs.—It is thought by some writers

that the females of this species are viviparous. I have watched the female insect ovipositing, and immediately examined the egg or sack under a microscope, using a high power, and could not detect any appendages; however, in twenty - four hours I noticed the presence of antennae and legs. The insect produces from two to four of these eggs or sacks in twentyfour hours, and the number produced by each female is from twenty to forty-three; the latter is the highest number I have found.

In the month of September, 1SS2,1 found a lemon at an orchard in Los Angeles county on which the larvae of thirty-nine male scale insects had located around the stem of the fruit, and as there was only one matured scale on the lemon this was evidently the number produced by one female, harvacolor, bright yellow; form, ovoid; length, one-eightieth of an inch; antennae, six jointed; anal setae, present.

Female: color, light or primrose yellow when the scale is formed, but as it reaches maturity il becomes a brownish yellow. The formation of the body is such that under the scale, when examined with a lense, ils appearance is that of a broken ring, but when ovipositing the posterior end of the abdomen extends beyond the circular line of the body. The color of the natural insect is shown through the nearly transparent scale from which it derives its common name—Red Scale.

Male: color of body, amber yellow, with dark marking on thorax; eyes, black.

Female red scale insect: color, yellow.

The young larvse can be found at all seasons of the year, and there are probably four or five broods in each year.

THE RED SCALE OF FLORIDA. (Aspidiotus ftcus—Riley, MSS.; Chrysom

phalus ficus—Riley, MSS. Ashmead.)

Order, Hemiptera; sub-order, Homop

tera; family, Coccidce.

[A species of scale insect infesting the branches, foliage and fruit of orange trees in Florida and the Island of Cuba.]

Professor Comstock describes this species as follows: "Female Scale.— Color, the part of the scale covering the second skin is a light reddish brown; the remainder of the scale is much darker, varying from a dark reddish brown to black, excepting the thin part of the margin, which is gray; exuviae nearly central, whitish in fresh specimens; form, circular, one line in diameter. Male Scale. — The scale of the male is about one-fourth as large as that of the female; the posterior side is prolonged into a thin flap, which is gray m color. (See United States Agricultural Report, 1880; and Ashmead on 'Orange Insects,' 1880."

THE LEMON-PEEL SCALE. (CAL.)

(Aspidiotus tierii—Bouche.) Order, Hemiptera; sub-order, Homoptera; family, Coccidce.

[A whitish circular scale insect, infesting the lemon, plum, cherry and currant; also the oleander, acacia, magnolia, etc.]

This species has been known to scientists as the "Oleander Scale,'' from which it derives its specific name, nerii. Within the last four or five years it has been found on the lemon, plum, cherry and currant; also on the acacia, magnolia, etc. It seems to prefer the fruit of the lemon, and in many cases infests the skin or peel to such an extent as to reduce its market value. California cannot claim a sole proprietary right to this pest, as lemons imported from Europe are often offered for sale in our market which are seriously infested by A. nerii.

Natural History.—The female scale is of a whitish color, and nearly circular, measures one line in diameter; exuviae or cast skin, yellowish, and near the center. Male scale, white, smaller and not as circular as that of the female. Egg, light yellow. Larva, yellowish white; length, one-eighty-tifth of an inch. Female, light yellow, with darker blotches; body, circular; abdominal segments appear as a pointed projection at one part of the circle. Male insect, winged; body, yellowish, with dark markings. The lemon-peel scale insect close^- resembles the red seal, and it is only by the difference in color that a person not thoroughly acquainted with the respective species can distinguish them.

Pergande's Orange Scale, (cal.) {Parlatoriapergandii—Comstock.) Order, Hemiptera; sub - order, Homoptera; family, Coccidce.

[A scale insect infesting the branches, foliage and fruit of citrus trees.]

I have found this species on the orange tree in Sacramento, but have not found it in any other part of the State.

The female scale is somewhat elongated in form, but nearly circular, the exuviae at one side of the center; color, grayish; exuviae yellow, and generally oval in shape.

The scale of the male is elongated and narrow; color, dirty white, exuviae at the anterior end. Female — color, purplish, with posterior end of the body yellowish, and is nearly as broad as long. Eggs— color, purplish; elongated; from nine to twenty found under each female scale. Larva — length, nearly one-nineteenth of an inch; color, purplish. Male — color, dark purplish.

THE (,'ITROS LEAP AND FRUIT SCALE.

(Mytilaspis citricola—Packard.) jSynonym, Aspidiotus citricola — Packard. Order, Himiptera; sub-order, Homoptera; family, Coccidce. [An elongated, slightly curved scale insect, infesting citrus trees.]

This species of scale insect has not been found on any of the citrus trees in this State, so far as I know, but it will be strange if it is not found in the near future. It is not a rare occurrence to find it on oranges, etc., which are imported from Europe, Australia and Tahiti, and offered for sale on fruit stands throughout the State.

The scale of this species is similar in form and appearance to that of the oyster shell bark-louse, excepting that it may be a little wider at the posterior end. Length of female scale, about one and one-half lines. The male scale is similar toother species of Mytilaspis in having a hingelike joint, posterior to the middle of the scale, so that by lifting the posterior part up the perfect insect can emerge.

THE SOFT ORANGE SCALE. (CAL.)

{Lecaniumhesperidum—Linnaeus.) Order, Hemiptera; sub-order, Homoptera; family, Coccidce.

[An oval flattened scale insect, infesting citrus trees, especially the orange.]

The soft orange scale is found in California in nearly every locality where citrus trees are grown. It infests the wood, foil

m

INSECTS INJURIOUS TO CITRUS TREES.

age and fruit. This, or a closely-allied species, is found on plants in hot-bouses.

Professor Comstock, in his Entomological Report of 1880, writes: "The male of this species has never been found, although it has been studied from the time of Linnaeus down."

In September, 1880, I prepared a dry mounting of a specimen of Lecanium hesperidum for microscopic use at the State Fair of that year. Early in the week a small insect was noticed coming from under a specimen beneath the glass, and finally released itself. It proved to be a male scale insect.

Natural History.—Female—a broad, oval scale, measuring from one and onequarter to one and one-half lines in length, widest at the posterior end; color, dark brown on top, and a lighter brown surrounding the margin. Two indentations on the margin on each side, and a large indentation on the posterior end. It has powers of locomotion similar to those of other Leeaniums. I have not found the egg of this species, but have found large numbers of the young larvse — as many as forty-five under one specimen. The young larvae appear about the first of May in the vicinity of Sacramento. Larva length, one-eighty-fifth of an inch; color, dark or dirty yellow; antennae, six jointed (some specimens appear to have seven joints); two anal setae.

Description. — Length of body, oneseventy-second of an inch; from front of head to apex of wing, one-twenty-fourth of an inch; posterior stylets, one-forlylifth of an inch, or one-half the length of body; color, body, immaculate golden yellow; eyes, dark or black; antennae (from the peculiar position in which they are placed I can only count seven joints), golden yellow and hairy; legs, golden yellow.

As it did not agree with the description of any of the male scale insects I had read of, or specimen males of aurantii, pemiciosus, persece, rapax, rosece or purchasi in my possession, I could only imagine that it was the male of L. hesperidum (be what it may, it came from under the L. hesperidum scale), and fortunately I preserved the mounting.

Cottony Cushion Scale, (cal.) (Iceiya purchasi—Maskell.) Order, 7/e

miptera; sub-order, Homoptera; family,

Coccidce.

[A white, cushion-like scale insect, feeding upon citrus trees, deciduous fruit trees, forest trees and on some varieties of vegetables.]

This species of scale insect I consider the most dangerous of any that infests fruit and other trees in California, as it may be said to be a general feeder. It is found on all varieties of citrus trees, deciduous fruit trees, on many varieties of ornamental trees, forest trees and shrubs; also on some varieties of vegetables. The apparent color of this scale insect at first sight is white, with a dark colored head. On examination it is found that the part indicated by the dark color is the insect, and the white portion a bag or case spun b3r the insect to conceal her eggs when deposited.

The females, after ovipositing (the egg case included), differ in size, some measuring six lines in length; but the general length is from three to four lines; width, one and one-half to three lines, and slightly tapering toward the posterior end. Each female deposits from two hundred to five hundred eggs. In one instance I counted seven hundred and three. The eggs are oblong-ovate in form, and of a pale red color.

Larva — color, body red; antennae, six jointed, clubbed at the apex, on which are six long hairs—color, smoky black; legs, smoky black (the joints of the antennae and legs are lighter in color than the balance); there are six long anal hairs; the margin of the body and back is also dotted with hairs; length of body, one-thirtyfifth of an inch.

The female insect during her growth assumes a variety of colors; principally yellowish red, with irregular blotches of white, green and yellow. At full growth, and before spinning egg case, she is ovoid in form. The hairs on the anal margin and sides are used as spinarets, exuding a cottony-like secretion, of which the egg case is formed. During her growth, and before beginning to spin her egg case, the females exude a honeydew, which forms a black smut on the branches and foliage. as described under the head, Black Scale. Male insect, winged; color, thorax and body dark brown, abdomen red; antennae dark colored, with light brown hairs extending from each joint; wings brown, irridescent.

TREATMENT FOB SCALE BUGS. [From the Bulletin of the Los Angeles Horticultural Commission.]

In all cases of infection from the white cottony cushion scale, it is recommended that the trees be thoroughly sprayed previous to any pruning. This plan is deemed the better one, because the danger of scattering and spreading the insects is much less than in the practice of cutting back or thinning out the trees previous to medicating. If properly and thoroughly used this first application will kill a considerable proportion of the bugs, many of which, if the trees were first pruned or cut back, notwithstanding the use of great caution and care in removing brush to the fire, would fall to the ground and seek adjoining trees or plants for food and breeding spots.

Use for spraying white scale, 35 pounds whale-oil soap, 4 gallons coal oil (110 fire test), to every 100 gallons of water. The coal oil must be made into an emulsion with the soap first, then add balance of soap and water, in the following manner: First, boil the soap in as little water as possible, as the soap must be thick to take up the coal oil and make a proper emulsion. When thoroughly dissolved and well boiled, place five gallons of this hot soap in an empty barrel, some distance from the boiling kettle, to prevent accident from fire; then add coal oil and churn vigorously for about ten minutes, with a stick with cross pieces about five inches wide at the end, forming a T. If the mixture at this time turns to a thick cream, pour in a little cold water—say two gallons— and churn again for a few moments; then add five or more gallons of water. Do not pour in water all at once, but a little at a time, and churn constantly while pouring in the water. This mixture, when prop* erly emulsified, will form a whitish, creamy substance. The most particular attention must be given to making the emulsion properly, otherwise the oil, not being incorporated with the soap and wa

ter, will rise to the top, and while portions of the tree will receive an overdose of kerosene, other parts will get little else than soap and water. The result will be unsatisfactory, for the coal oil must go with the soap to do effectual work in killing the bug.

As soon as practicable after the first application, proceed to cut back and thin out the tree, burning the brush as near the tree from which it is taken as possible without danger of injury to it. A large canvas under the tree during the pruning will, if carefully disinfected at the finish, prove of considerable benefit. A band of rope, thoroughly smeared with coal tar, about the trunk of the tree, first putting a band of leather or thick cloth over which to tie the rope, will prevent the Insect from ascending, and tend to indicate its presence and location for future treatment. Cases of ordinary infection can undoubtedly be cured if the above is carried out faithfully and to the very letter, and by keeping such close watch over the trees that the reappearance of the bug is at once followed by an application of the spray, before any time has lapsed for breeding and spreading. In aggravated cases of infection, where the bug has a strong hold upon the tree, topping, careful brush burning and hand scrubbing must be resorted to. But even in such cases the use of the spray at first would much simplify the work and lessen the danger of scattering and spreading the scale bugs. It is highly necessary to success that all weeds in the vicinity of infected trees should be carefully gathered up and burned.

For the red scale, July and August are the best months to spray in, as they hatch during May and June. Use thirty-five pounds of soap and three gallons coal oil to every one hundred gallons of water. If sprayed in September or October add five pounds of soap.

The best months to spray for black scale are September and October. They hatch through July and August. Use thirty pounds soap and two and one-half gallons coal oil to every one hundred gallons water. Thinning out and cutting away all surplus wood will do much towards relieving the trees from black scale. Care should be taken to strain the wash through fine wire cloth, otherwise frequent stops will be necessary to clear the spray nozzle.

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