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TWENTY-NINTH FRUIT-GROWERS' CONVENTION. 



alive (that is, the eggs hatch within the parent scale), as in the San 

 Jose scale. In all cases the young scale insects — usually yellow, oval 

 in form, very minute, a mere speck — move about, may crawl upon foot 

 of bird or insect and be borne to other plant or tree, or mayhap are 

 carried by wind to other pastures. Soon they insert their long beaks 

 into leaf or tender twig and commence vigorously to pump the sap or 

 life from the host plant. Thus they seem to be permanently anchored 

 (though they will be seen to move if the leaf or twig dries up), even 

 until well grown. Soon after anchorage, they secrete the well-known 

 honey dew, which attracts a black fungus, and we are vexed by the 

 appearance of the black smut on our oranges or lemons. This nectar 

 also attracts bees, Avasps, and ants, which repel insectivorous birds, and 

 thus the young scale insects are protected. Usually, in less than a 

 year, often much less, they become full grown, have lost their legs and 

 antennae, and now the eggs again appear, either under the scale or 

 within the mother insect. 



There are three distinct types of coccids or scale insects. The first 

 type are those which always move freely from the time of hatching 

 until full maturity. The mealy bugs and cottony cushion scale are 

 examples. In the second group, the scale is the insect, and it moves 

 little, if any, after it once settles to work. These are often referred to 

 as the unarmored scale. The black and apricot scales are examples. 

 Here, when we touch the scale, we touch the insect. The third division 

 is armored; that is, each insect is protected by a scale, separate and 

 distinct from the insect. This covering consists of the first two molts, 

 or cast-off skin, which form the little nipple-like projection of the scale, 

 and a border of fibrous secretion which completes the scale. Here, we 

 do not touch the insect when we touch the scale. We must raise the 

 scale to find the insect, which is just beneath it. The red scale and 

 San Jose scale are illustrations of this group. It goes without saying 

 that the armored scale, protected as it is, may be more difficult to kill 

 than are the others, although all are very tenacious of life. It is a 

 curious fact that the males of all the coccids are unique among insects. 

 At first, they are scale-like, similar to the females, although the form 

 and size of the male generally differ from that of the other sex. At 

 last they come forth with wings, but have only a single pair. The 

 males are usually much less common than are the females. In some 

 species, the males seem to be largely wanting. 



Injurious Species. — Of the first group, I am familiar with the follow- 

 ing California species: Mealy bugs, which infest the citrus orchards; 

 the cottony cushion scale, which attacks not only the orange and lemon, 

 but also many other trees and plants; the maple Pulvinaria, which 

 infests grapes and apple trees. Of the second group, we have the black 

 scale, the soft brown scale, the hemispherical scale, and the Coccus 



