OF INSECTS- 223 



ON THE GENERATION OF INSECTS. 



Of the Parts of Generation. 



Insects cannot be said to have external parts of generation; for, 

 although the penis in the male can be made to project, yet in its accus- 

 tomed situation it is in the abdomen. 



The females have no external parts, excepting the opening of the . 

 vagina, which is hid by the two last scales 1 . The opening of the anus 

 in the beetle is, I believe, in the same horny apparatus with the vagina. 



Male Parts of a large Moth. 



At the termination of the back is a strong horny hook that bends 

 downwards, in the curve of which opens the anus. There are two 

 lateral, but smaller hooks. The penis is a horny body which comes out 

 under the anus, and has a spongy ' glans.' It moves backwards and 

 inwards in a horny groove or ring, which is fixed in a pretty large 

 horny apparatus. 



In a large green grasshopper [Acrida (Phasgoneura) viridissima] with 

 hardly any wings and with a long tail [ovipositor], which divides the 

 anus from the vagina, I found a bag between the rectum and vagina 

 whose opening was just at the verge of the vagina, which I suppose is 

 the ' depository of the semen ' \ 



Male Parts of the Rose-beetle \_Cetonia aurata]. 



The male parts consist of a penis, testes, and other glandular ducts. 

 They are all contained within the abdomen in their natural state or 

 position, but the penis may be made to project 3 . Within the two last 

 scales of the abdomen there is a horny apparatus for the projecting 

 muscles of the penis to act from, which may be called their pelvis. The 

 penis is large, composed of a horny substance, flat upon the upper and 

 lower surface from edge to edge ; it is a little bent, the hollow of which 

 curve is on the under surface, so as to be better adapted to enter the 

 vagina of the female, which is underneath 4 . Through the centre of this 



1 [The female Lepidoptera possess two sexual orifices, one behind the other, of 

 which the hindmost serves for oviposition, the foremost receives the male organ in 

 coif if. ] 



2 [It is the ' spermatheca ' (Hunt. Prep. No. 3168), and is the homologue of the 

 '' bag" in the silk-moth, which Himter experimentally proved to contain the semen 

 of the male. See Animal Economy, p. 461 . Also my ' Lectures on Invertebrata,' 

 for ' female parts ' of Orfhoptera, p. 404, 8vo. 1855.] 



3 [Hunt. Prep. No. 2328 {Bombyx Moll).] 

 i [On the ventral surface.] 



