ti6 



nation, according to Ue Geer and Bonnet, produced living female 

 young ones. This spontaneous generation was repeated to the tenth 

 generation. After this a generation of males and females again made 

 their appearance. 



On this subject he could not do better than quote Professor Von 

 Siebold, whose work on the subject of Parthenogenesis had been trans- 

 lated by Mr. W. S. Dallas. Von Siebold says : " It is well-known 

 that in the Aphides, a sexual generation represented by separate 

 males and females, is followed by a series of generations only in- 

 cluding a single form, which proceed from each other in manifold 

 repetition, without any previous copulation, until after about seven to 

 eleven such generations a generation of males and females again 

 makes its appearance. 



" Steenstrup regarded these forms of Aphides, which are capable 

 of reproduction without the influence of the male generative organs, 

 and which had been previously looked upon as virgin female Aphides, 

 as Nurses, and consequently as those members of an animal species 

 subjected to an alteration of generations which are capable of pro- 

 ducing young in the asexual state. Those Aphides which bring forth 

 living young, without a preliminary copulation, are in reahty quite 

 different in their organization from the female Aphides, which lay eggs 

 capable of development after the act of copulation. 



" In the viviparous Aphides those organs, specially from which 

 the living young are produced, have quite a different form and 

 organization from the sexual organs of the oviparous Aphides ; 

 so that in opposition to the ovaries, the products of which (eggs) only 

 become capable of development by the action of the male semen, we 

 may with perfect justice indicate the organs as germ stocks, which 

 are capable of producing young of themselves without the influence 

 of male fertilizing organs. 



" These nurselike viviparous Aphides therefore, which, instead of 

 ovaries, bear germ stocks in their interior, are also destitute of the 

 seminal receptacle which occurs universally in the female of insects 

 and plays an important part in the fecundation of eggs." 



The terms "germ stocks " and " germ body "had been used to 

 distinguish the reproductive organs of the viviparous asexual Aphides 

 from the eggs and ovaries of the oviparous female Aphides. 



Thus much on the subject of spontaneous generation of germ 



