86 The Conditions of Infusorial Life. 



quite independent of his main argument, it will be interesting 

 to show what his views really are, and we find them abundantly 

 stated in his work entitled " Heterogenic/' published at Paris 

 in 1859. He declares that he has never said a word to lead any 

 one to suppose that he believes in the generation of animated 

 beings without the aid of vital power ; that, on the contrary, he 

 has always thought that organized beings were animated by 

 forces which were in nowise reducible to physical or chemical 

 forces (p. 428). He considers generation, or the manifestation 

 of life on the globe, to have been one of the first acts of crea- 

 tion, and he believes that similar acts are continually taking 

 place. As a rule, heterogenists have developed a system ad- 

 verse to great convulsions in Nature ; but M. Pouchet adopts 

 what may be called spasmodic theories of geology, and he tells 

 us that the manifestations of spontaneous generation do not 

 now reach the same proportions as in ancient times ; that they 

 have grown smaller like other telluric phenomena, because we 

 have not now in fermentation that immense mass of dead matter 

 resulting from " so many cataclysms and funerals of animals ; 

 and therefore, instead of the gigantic races which surged up 

 from the midst of agitated elements, we only witness the pro- 

 duction of the lowest forms " (p. 462). 



As will presently be seen, this strange supposition is a most 

 unphilosophical induction from some interesting experiments on 

 the effect of mass, in a fermenting material, in determining the 

 kind of organism which will be produced. M. Pouchet further 

 contends that his views harmonize with the system of Nature, as 

 exhibited in the generation of the higher kinds of animals ; and 

 with the opinions of certain physiologists who affirm that in a 

 great number of animals of all classes, the " first lineaments of 

 ovules" have no adhesion to the internal apparatus which pro- 

 duces them, and that the ovules form themselves, under the in- 

 fluence of a special force, in the midst of a granular fluid secreted 

 in the cavity of the apparatus (p. 374) . According to this hypo- 

 thesis, the mother does not form the egg, but it develops itself; 

 and the maternal apparatus exerts a dynamic force upon it, winch 

 reproduces the original type (p. 378). In further exemplification 

 of these views, he asserts that the ovary is the seat of an inde- 

 pendent genetic force, and that, in like manner, organic matter 

 may be the seat of an analogous force, so that the generation of 

 ovules from what he calls "the proligerous pellicle, or scum 

 which appears on infusions of vegetable matter as fermentation 

 proceeds, is precisely analogous to that of natural ovules in 

 the ovary" (p. 378). 



Having explained the chief points of M. Pouchet' s theory of 

 heterogenesis, his method of proof next engages attention, and 

 this may be described as a process of elimination. He endea- 



