GENESIS. 



215 



Ttneida % parthenogenesis appears to be a normal process 

 indeed, so far as is known, the only process ; for of some 

 species the males have never been found. 



A general conception of the relations among the different 

 modes of Genesis, thus briefly described, will be best given 

 by the following tabular statement. 



fHomogenesis, winch is Gamogenesis 



GENESIS is 



or 



f Gamogenesis 



alternating 

 Hetcrogenesis, which is \ 



with 



[ Agamogenesis 



Oviparous 



or 

 Ovo-viviparoua 



or 

 Viviparous 



Parthenogenesis 



Pseudo-parthenogenesis 

 or f Internal 



Metagenesis -j or 



( External 



This, like all other classifications of such phenomena, pre 

 sents anomalies. It may be justly objected, that the processes 

 here grouped under the head agamogenesis, are the same as 

 those before grouped under the head of discontinuous develop 

 ment ( 50) : thus making development and genesis partially 

 coincident. Doubtless it seems awkward that what are from 

 one point of view considered as structural changes, are from 

 another point of view considered as modes of multiplication.* 



* Prof. Huxley avoids this difficulty by making every kind of Genesis a mode 

 of development. His classification, which suggested the one given above, is ar 

 follows : 



( Growth 

 fContinuous - 



( Metamorphosis 



Development Metagenesis 



( Agamogenesis J 



[Discontinuous ( Parthenogencccn 



( Gamogenesia 



