AND THE LOWER ANIMALS. 253 



solid envelope according to the accidents they are 

 likely to incur, and which is capable of preserving 

 them from external influences ?* Certainly not. Not 

 more so than an ovum becomes a bud, because it 

 never acquires a shell before it is transformed and 

 developed within the mother's body. 



But if these reproductive bodies are buds, and not 

 ova, it then follows that development without the 

 intervention of the male element occurs in the phe- 

 nomena just considered. This is not a case of par- 

 thenogenesis, but one of geneagenesis. 



This conclusion appears to me to be clearly deducible 

 from these two series of researches, evidently carried 

 out with extreme care, and which have been more 

 strictly compared with each other than all the rest 

 which have been published on this subject.f Its 



* The envelopes of these pretended ova evidently vary under the 

 conditions alluded to. They would be useless to the internal bud 

 of the aphis, which is developed within the organs of the mother. 

 Therefore they are not present. The internal buds of the peach- 

 tree kermes are as well protected as the true ova, although they 

 do not undergo their transformation till they have left the parent's 

 body. Between these two extremes we find the internal bud of 

 the orange-tree Kermes or Lecanium, which is almost entirely 

 developed within its parent's body, and has acquired its perfect 

 form a few hours after being deposited. Hence it is protected only 

 by a single envelope, which Lubbock compares to the vitelline 

 membrane (" On the Ova and Pseudova, &c"). Now that atten- 

 tion has been directed to this point, I am convinced that many 

 other instances will be found which may be serially arranged in 

 the group of phenomena referred to. 



t Professor Huxley and Mr. Lubbock, between whom a friend- 

 ship exists, evidently commmnicated the results of their researches 

 to each other. It was on the invitation of the first that the inte- 

 resting investigations of the second were carried out ; and in his 

 turn, Huxley devoted his attention to the results obtained by 



