52 VITAL FUNCTIONS OF PLANTS. [LECT. II. 



" with organization, which animals and plants 

 " possess in common, of continuing life.' 1 Both 

 animals and vegetables communicate it to their 

 offspring. By viviparous animals it is communi- 

 cated to the foetus long before its expulsion from 

 the uterus; by the oviparous, to the punctum sa- 

 liens, which is afterwards the chick, before the egg 

 receives its shell ; and by vegetables, to the em- 

 bryo contained in the seed, long before this has 

 obtained perfection in point of size, and is sepa- 

 rated from the plant. In these instances the 

 functions of the new beings either immediately 

 commence, as is the case in the foetuses of vivi- 

 parous animals ; or they do not commence till the 

 necessary agents are present for evolving the proper 

 organs, as yet unformed or imperfect, as happens 

 in eggs and in seeds: but, in both cases, it conti- 

 nues for a definite time only, and is then lost. 

 During its continuance both animals and plants 

 preserve their organization, and resist those che- 

 mical attractions or affinities which subsist be- 

 tween the different component parts of their bo- 

 dies ; and which, immediately whejj life ceases, 

 act ; and, by dissolving the old combinations, pro- 

 duce new ones, by the processes of putrefaction 

 and fermentation, and render back their elements 

 to the inorganic kingdom. We do not mean, how- 

 ever, to assert that organized bodies do not admit 

 of chemical combinations, during life ; as it can- 

 not be denied that more complicated and diversi- 



