Some insects injurious to forests . x. There is a large fleshy tubercle at each side ofthe prothorax. The legs are folded underneaththe body. The first pair is borne by the prothorax, the second bythe mesothorax, and the third by the metathorax. The mesothoraxbears a spiracle in the same position as that of the larva, and the first 5abdominal segments bear spiracles; the rest apparently do not. Uponthe dorsal surface all segments of the thorax and abdomen bear ventral surface of all abdominal segments, except the last, is last abdominal segment, which occupies the extre
Some insects injurious to forests . x. There is a large fleshy tubercle at each side ofthe prothorax. The legs are folded underneaththe body. The first pair is borne by the prothorax, the second bythe mesothorax, and the third by the metathorax. The mesothoraxbears a spiracle in the same position as that of the larva, and the first 5abdominal segments bear spiracles; the rest apparently do not. Uponthe dorsal surface all segments of the thorax and abdomen bear ventral surface of all abdominal segments, except the last, is last abdominal segment, which occupies the extreme posterior endof the body, has a peculiar triangular shape. One of the points of thetriangle is prolonged upward into a sharp, chitinized spine. The twolower points of the triangle are armed with several chitinized anal segment occurs directly beneath the last abdominal segment,and is inclosed on three sides by the latter. A strongly marked sexualdifference is to be found between the anal segment of the male and that. Fig. 17.—The pine sawyer:Pupa. About twice nat-ural size. (Original.) THE SOUTJ-IKliX PINE SAWYER. 49 of the female. In the male this segment shows merely the anal open-ing. In the female two globular tubercles are borne side by side onthis segment. SEASONAL HISTORY. There are four stages in the life of the sawyer, first, the egg (fig. 15);second, the larva (fig. 16); third, the pupa (fig. 17); fourth, theadult (fig. 14). In southern Mississippi the egg-laying period lasts from about thefirst of March to the middle of October. In some cases eggs maybe laid earlier or later than the dates given, but the main activity inegg-laying will be found to be comprised within this period. Theyoung larva3 hatch from the eggs in about five days after the eggs The length of time from the hatching of the young larva to thetime of maturity and change to the pupa appears to vary considerablyin different individuals. The comparative periods of time s
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectinsectp, bookyear1910
