OVIPOSITORS OF INSECTS, 



339 



Fig. 170. 



Female generative organs of the Queen 

 Bee: a a, ovigerous tubes; 66, oviducts; 

 c, spermatheca ; e, vagina, or common ex- 

 cretory duct. 



the favoured male dies, and, by a simultaneous butchery, all the other 

 males, or drones as they are com- 

 monly designated, are destroyed by 

 the working inhabitants of the hive. 

 The quantity of the fecundating 

 liquor, therefore, supplied by one 

 connexion must serve to fertilize all 

 the eggs produced during the life- 

 time of the queen-bee ; and for this 

 purpose it is stored up in the 

 spermatheca (fig. 170, c) ; so that, 

 how numerous soever may be the 

 eggs formed, they are all vivified as 

 they pass out through the oviducts 

 (b, e), and thus come in contact with 

 the orifice of the reservoir of semen. 



(889.) In Meloe variegatus (fig. 164) the ovaria (d) consist of wide and 

 capacious sacs, covered externally with innumerable glandiform vesicles, 

 opening into the cavity of the ovary (e). The gluten-secretor (h) and 

 the spermatheca (g) are seen, as in Melolontha, appended to the common 

 oviduct (/); but the spermatheca has a small accessory vesicle (i) 

 connected with it, not found in the former examples. 



(890.) In many insects, especially of the Hymenopterous order, the 

 generative apparatus is terminated externally by peculiar instruments 

 provided for the purpose of introducing the eggs into a proper situation. 

 This is particularly remarkable in the Ichneumons, which deposit their 

 ova in living caterpillars ; and in the Saw-flies (Tenthredo), whose eggs 

 are insinuated into the substance of the leaves, or even of the branches 

 of trees. To describe all the contrivances employed for this purpose 

 would lead us far beyond our prescribed limits : one example of an 

 organ of this description must suffice. 



(891.) In Sir ex gigas (fig. 171) the ovipositor consists apparently of 

 three pieces of considerable length, seen in the figure to project from the 

 inferior margin of the abdomen. Of these pieces, two form a sheath 

 enclosing a third, called the terebra, or borer, which in the Tenthredo 

 contains two saws of extremely beautiful construction, as we learn 

 from an account of them given by Professor Peck, and quoted by Kirby 

 and Spence*. The original description, which it would be unpardonable 

 to abbreviate, is as follows. " This instrument," says Professor Peck, 

 " is a very curious object ; and, in order to describe it, it will be proper 

 to compare it with the tenon-saw used by cabinet-makers, which, being 

 made of a very thin plate of steel, is fitted with a back to prevent its 

 bending: the back is a piece of iron, in which a narrow and deep 

 groove is cut to receive the plate, which is fixed. The saw of the Ten- 

 * Introd. to Entom. vol. iv. p. 161. 



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