CHAPTER III. 



ON THE ORIGIN OF ANIMAL NATURE. 



628. The commencement of animal nature is termed its 

 generation ov procreation. (Baumgarten^s 'Metaphysics/ § 311.) 



Consequently, an animal in the widest sense of the term is 

 [produced so soon as au organised body is capable of being 

 [moved by means of the animal-motor forces of its proper animal 

 lachines. No animal can thence arise, not even the insen- 

 ient, unless provided at least with nerves and vital spirits, or 

 [their analogues, of which the vis nervosa of impressions is a 

 [peculiar property (1 5, 604) . No insentient animal can become 

 I sensational, unless furnished with brain and its vital spirits, or 

 an analogue, and of which the animal -sentient forces (10), are 

 a peculiar property. A sensational animal can only become a 

 rational animal when it attains to the power of regulating its 

 jbody by intellectual conceptions and volitions (76,574, 96). 



629. Every animal springs from one like itself. The mi- 

 nutest, with few, if any, organs and functions, and a very brief 

 life, are generated after a very simple mode. They are pro- 

 duced without any difference of sex by fissiparous generation. 

 In others, the mode is oviparous, and of these a large class is 

 hermaphrodite, the same individual containing both male and 

 female organs. In a larger class, the two sexes are distinct. 

 The females of cold-blooded animals deposit their ova, and then 

 they are fructified by the male ; in warm-blooded animals, the 

 ova are fructified in the uterus, and may be incubated either 

 within or without that viscus ; in some genera and species of 

 animals either method is followed, and they are both oviparous 

 and viviparous. 



630. The generation of an animal always takes place by one 

 similar to it, and by which the essential constituents of its 

 animal nature are communicated to it. The origin of an animal 

 machine and its vital spirits, whether it be nerve or brain, is 

 one of the hidden secrets of nature, of which we are totally 

 ignorant. 



