. Cassell's natural history. Animals; Animal behavior. THE GALL PLIES ^^ Tlie Cynipiiliv arc- cliaractei'ised by their unbent anteunio, which are usually thread-like, ami composed of from thirteen to sixteen joints, the number being frequently greater in the males than in the females. Tl>e wings show no submarginal cells, except the apical one, and sometimes a very .small one just within the stigma, at the apex of the discoidal cell. The abdomen, which is usually short, is strongly compressed, and only the fii-st, or first and second segments, are greatly developed, the remainder being retr
. Cassell's natural history. Animals; Animal behavior. THE GALL PLIES ^^ Tlie Cynipiiliv arc- cliaractei'ised by their unbent anteunio, which are usually thread-like, ami composed of from thirteen to sixteen joints, the number being frequently greater in the males than in the females. Tl>e wings show no submarginal cells, except the apical one, and sometimes a very .small one just within the stigma, at the apex of the discoidal cell. The abdomen, which is usually short, is strongly compressed, and only the fii-st, or first and second segments, are greatly developed, the remainder being retracted within these, so that only their edges project. These fully- develoi)ed segments are much longer at the back thantoward;; the ventral surface, so that the posterior margins of the segments, and that of the abdomen, become very oblique, especially in the female, jind thus the ovipositor comes to issue from near the middle of the lower surface of the abdomen. Its arrangement is very peculiar. The last visible segment is produced within the others nearly to the base of the abdomen, where it has articulated to it a small triangular chitinous plate, to which the sheath of the ovipositor is also movably articulated. This sheath, as in the other Entomophaga, consists of two flattened joints on each side of the ovipositor, and the apical joints project from the abdomen, and, passing up along its posterior margin, produce the appearance of a sort of cleft. Within this the ovipositor lies, so that its point Is directed upwards. By the action of muscles upon these parts, the ovipositor, which, in repose, is bent more or less in a spiral form, is pushed out from between the side-pieces forming the sheath when it is being employed in egg-laying. It consists, as in the Ichneumons, itc, of a principal superior piece, and two smaller pieces below, the whole arranged so as to form a triangular tube, for the passage of the egg. The latter is remarkable in its structure. It is considerably
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Keywords: ., bookcentury1800, bookdecade1890, booksubjecta, booksubjectanimals
