Page:Insects - Their Ways and Means of Living.djvu/155

 AND MEANS OF LIVING

male (B, Tes) in which the spermatozoa reach their com- plete growth. Appropriate ducts connect the ovaries or the testes with the exterior near the rear end of the body. The female usually has a sac connected with the egg duct (A, Spm) in which the sperm, received at mating, are stored until the eggs are ready to be laid, when they are

VIII IX X Cet" I I / .-A t I

Fxc. 74- The oviposltor of a long-horned grasshopper, a member of the katydid family, showing the typical structure of the egg-laying organ of female insects A, the ovipos'itor (Ovp) in natural condition, projecting from near the posterior end of the body B, the parts of the ovlpositor separated, showing the six component pieces, two arising from theeighth abdominal segment (FIII), and four from the nlnth (IX). /ln, anus; Cet, cerci; IX, ninth abdominal segment; Ovp, ovipositor; FgO, vaginal opening; FIH, eighth abdominal segment; X» tenth abdominal segment extruded upon the latter and bring about fertilization. The egg cells ordinarily are all alike, but the spermatozoa are of two kinds; and according to the kind of sperm re- ceived by any particular egg, the future individual will be male or female.

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INSECTS