. Elementary text-book of zoology, tr. and ed. by Adam Sedgwick, with the assistance of F. G. Heathcote. 540 INSECTA. Be easier movement. They have larger eyes and antennae, and their colours are brighter and more striking. When there is a pronounced dimorphism the females are apterous, and their form approximates to that of the larva (Coccidce, Psyckidce, Strepsiptera, Laanpyris), while the males are provided with wings. The female generative organs are composed of paired ovaries and oviducts, the unpaired oviduct, the vagina and the external genital apparatus. The ovaries are elongated tubes
. Elementary text-book of zoology, tr. and ed. by Adam Sedgwick, with the assistance of F. G. Heathcote. 540 INSECTA. Be easier movement. They have larger eyes and antennae, and their colours are brighter and more striking. When there is a pronounced dimorphism the females are apterous, and their form approximates to that of the larva (Coccidce, Psyckidce, Strepsiptera, Laanpyris), while the males are provided with wings. The female generative organs are composed of paired ovaries and oviducts, the unpaired oviduct, the vagina and the external genital apparatus. The ovaries are elongated tubes, in which the eggs originate. The ova lie one behind another in a single row like a string of pearls, increasing in size from the blind end to the opening into the oviducts (fig. 91, a). The arrangement of these ovarian tubes presents extraordinary variations, and there thus ori- ginates a great number of dif- ferent forms of ovary, which have been described principally in the beetles by Stein. The number of the ovarian tubes also varies exceedingly, being least in some Rhynchota, and then in the butterflies, the latter having on each side only four very long ovarian tubes, which are many times folded (fig. 448). At their lower ends the ovarian tubes on either side open into the dilated commence- ment of the oviduct, which joins with that of the other side to form a median oviduct. The lower end of the latter repre- sents the vagina, and often receives, near the genital aperture, the ducts of special cement and sebaceous glands (//landidat selxtcecv), the secretion of which is used to surround and fasten the eggs which are about to be laid. In addition to these glands, the unpaired efferent duct of the genital apparatus is very commonly furnished with one or several usually stalked receptacula seminis (fig. 449), in which the semen, often introduced in the form of spermatopJwres, retains its fertilizing properties for a long time, sometimes for years, under the in-. FlG. 448.
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