Forest entomology . idea of the repro-ductive organs of accompanying figuresand explanation have beenselected because they are notonly large insects, but arborealin their habits. It may alsobe noted that, as regardsinsects, the hive bee has beencarefully worked out in thisrespect, so that reference toany of the more importantworks on the bee would befound very helpful. Genital organs. — Thefemale, as in other Arthro-poda, possesses a pair ofovaries. Each consists of avarying number of tubules(ovarioles), which usually ex-tend like fingers from theanterior end of the ov
Forest entomology . idea of the repro-ductive organs of accompanying figuresand explanation have beenselected because they are notonly large insects, but arborealin their habits. It may alsobe noted that, as regardsinsects, the hive bee has beencarefully worked out in thisrespect, so that reference toany of the more importantworks on the bee would befound very helpful. Genital organs. — Thefemale, as in other Arthro-poda, possesses a pair ofovaries. Each consists of avarying number of tubules(ovarioles), which usually ex-tend like fingers from theanterior end of the ovariole is surroundedby a thin membrane, and isimmature anteriorly, consist-ing of small homogeneouscells ; farther back there arelarger cells, young ova, lyingin the middle of the tube, and surrounded by smaller cells, whichprovide them with nutriment, and also secrete the shell (chorion)for the fully developed egg. The mature ova occupy the posteriorends of the ovarioles, and pass thence into the oviduct. When an. Fig. IS.—Food canal of cockroach. salivary glands and reservoir ; c, crop (the gizzardbelow it); cos, cpecal tubes (below them thestomach); k, kidney tubes; i, intestine; r, rec-tum. Twice natural size. (FromThe Cockroach,by Miall and Denny.) 16 FOREST ENTOMOLOGY. egg passes into the latter, the corresponding portion of the ovariantubule shrinks, and thus the egg next in front is brought nearer tothe duct. The two oviducts unite to form an unpaired portion, the vagina, which opens ventral to theanus, either freely on the surfaceor into a cloaca, an invaginationoccurring at the hinder end ofthe body. There is usually anevagination of the vagina whichserves as a receptaculum seminis,and one or a pair of accessoryglands, which secrete either asticky fluid to attach the ova toforeign bodies, or the mucus sur- Fig. 19.—Diagrams of the heart of an insect. -,. ,, / • •„„„+„ b rounding them {, m insects which lay their eggs in water). Sometimes there is
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