In addition to the organs above enumerated as composing the male system in insects, we may notice appendages which are found in some tribes which materially assist in effecting the intercourse of the sexes : these are named prehensores, and serve to seize and secure the female during coitus. These holders assume a great variety of shapes, and likewise are rently disposed according to circumstances. They generally surround the aperture through which the penis is extruded, but in Libellula the mode in which the sexes embrace each other renders additional security indispensable; in thus tribe, therefore, besides the anal prchen sores, an additional pair of forceps is placed under the second abdominal segment. The prehensores are generally two in number ; hut in many Lepidoptera, Conopis and Libelltila, three are placed around the anus. In Culex there are two pairs. In Locusts morbillos,e there are five, and in Formica six holders. In some tribes, as Megachilis, Agrioniclas, and Locusta, they are retracted within the abdomen when not employed.
In insects the ovigerous or female generative apparatus consists likewise essentially of tubes or mca, the arrangement of which is tolerably uniform. They may be divided into the ovaria, the oviducts, the spermotheca, or receptacle for the seminal fluid of the male, the accessory glands, and the ovipositor, which latter is, in many insects, an instrument adapted to intro duce the eggs at the period of their extrusion into situations suited to their developement.
The ovaria are double throughout the whole class, each being composed of a variable num ber of membranous tubes arising from the oviduct, Itifferschweils considers the ovaries to be formed upon two primary types, being either flogctlybrm, that is, composed of conical tubes of equal length, which are inserted at the same place at the extremity of the oviduct, as in the Lepidoptera, the Bee, &c.; or racemose,
consisting of short conical tubes, so proceeding from the primary branches as to render the ovary nteemose or pinnated, such as they are in many Ncuropteru, Caleopteru, and Diptcru.
The number of tubes composing each ovary varies in different genera and species ; some times there are but two, at others four, five, six, eight, or twelve, and in the more prolific insects this number is much increased ; thus, in Acrida viridissitna there are thirty, and in the hive-bee not fewer than a hundred and fifty caeca in each ovarian packet. The number of eggs will of course depend upon the number and divisions of these ovarian tubes, and thus while some insects only lay two, four, or six eggs, others will produce sixty or seventy, and some gregarious insects a much greater num ber : thus the hive-bee will probably give birth to many thousand young, and in the Tennite ant ( Tcnues bellicnsus) the fecundity of the female is absolutely incalculable. This extra ordinary fertility renders indispensable certain restrictions which we find imposed upon this numerous class, tending materially to limit their multiplication. Thus, through out the whole race one generation only is pro.. duced from the same insect, the business of reproduction being usually the termination of its existence; and in the most prolific tribes, namely, those which live in society, as the 13,c and the Termite, one female only in each com munity is found to be fertile, the sexual organs of all the rest remaining in a mdimentary or undeveloped state, although capable of de velopment, should the destruction of the queen render such a provision for the preserva tion of the race indispensably necessary. (See