APPENDIX D. cv 



c. One or more germs appear to form occa- 

 sionally in animals which are about to 

 conclude their existence. Their forma- 

 tion seems to be the last vital act on the 

 part of the parent organisms, which gra- 

 dually perish as the development of their 

 offspring progresses. 



1. According to Nicolet 1 , an ovum forms, 



under these circumstances, by the ag- 

 gregation of previously scattered gran- 

 ules, and the subsequent development 

 of a membrane around such a granule 

 heap. 



2. Pouchet also speaks 2 of the presence of 



ova, under such circumstances, in spe- 

 cimens of the genera Kolpoda and Ke- 

 ronea, though he does not seem to have 

 traced their mode of formation. 



3. Lastly, J. Haime states that he has seen a 



body of this kind appear shortly before 

 the death of Paramecium aurelia, which 

 very soon broke up into about sixty 

 minute ovules or zoospores. These in- 

 creased in size, burst the sac in which 

 they were contained, and afterwards 

 escaped from the disintegrating body of 

 the parent through a rupture in its in- 

 tegument. 



Thus almost every conceivable mode of reproduction 

 seems to take place by turn in these creatures, and the 

 developmental modifications which they have been seen to 

 undergo are so many and so various as to make it almost 



1 ' Arcana Naturae/ p. 30. 2 ' Het^rogenie,' p. 400. 



