. Annual report of the Commissioner of Agriculture ... Agriculture -- New York (State). 322 Report of tjik Department of Entomology of the and more or less embrowned about the disk. Length to tip of hemelytra 6 mil- lims. Humeral breadth, If ;23 LIFE HISTORY. As is common to insects of this group the nymph passes through five stages, attaining wings at the fifth ecdysis. The minute yellow larvoe make their appearance during the period when the trees are coming into blossom and until pollination is completed and the young fruits are of the size of filberts. The time for the emergen
. Annual report of the Commissioner of Agriculture ... Agriculture -- New York (State). 322 Report of tjik Department of Entomology of the and more or less embrowned about the disk. Length to tip of hemelytra 6 mil- lims. Humeral breadth, If ;23 LIFE HISTORY. As is common to insects of this group the nymph passes through five stages, attaining wings at the fifth ecdysis. The minute yellow larvoe make their appearance during the period when the trees are coming into blossom and until pollination is completed and the young fruits are of the size of filberts. The time for the emergence of the insects in their maximum numbers has, during the past several years, been largely coincidental with the dropping of the petals, but probably this will not hold true under all seasonal conditions. In 1910 hatching of eggs occurred during the period of May 3 to May 19, and in this interval the trees were in full bloom on May 5, and blos- soms began to drop on May 9. In 1911 and Fig. 25a.—L. pratensis, c L •> Adult. 1912 pears blossomed on May 11 and 12 and petals began to drop on May 15. During each year nymphs of the first instar were abundant at the later date, and within one week the insects, with hardly an exception, had transformed to the next stage. Nymphs of the second instar differ from the preceding stage chiefly in size and they appear in about one week after the eggs are hatched. In 1911 many of these nymphs were seen as late as May 31, while in 1912 they were becoming very abundant on May 22. At the next ecdysis the young insects become green in color while the integument appears to be tougher and more horny than before. The nymphs from now on are less active and remain quietly upon the foliage or on the fruits for considerable periods of time. Specimens reared in the laboratory completed this instar in either 6 or 7 days. ^The adult of pratensis is a small, oval, sucking insect about one-fifth of an inch in length. It differs from invitus in size, be
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