38 LECTURE I. 



and rest in the night, yet also some vegeta- 

 bles like some animals rest in the day and 

 are in action during the common season of 

 repose. 



We see animals scarcely differing from 

 vegetables in their functions, like them 

 doomed to a stationary existence, with even 

 less appearance of organization than we 

 usually discover in vegetables, and of a 

 structure so simple as to admit of propaga- 

 tion like vegetables by cuttings. Yet in 

 all the diversity of living beings we recog- 

 nize certain processes peculiar and essential 

 to life ; as the power of converting other 

 kinds of matter into that appropriate to the 

 individual it is to form and support ; the 

 power of distributing the nutriment, thus 

 converted, to every part for its formation 

 and supply ; the ventilation, as I may call 

 it, of the nutritive fluids ; the power of pre- 

 paring various dissimilar substances from 

 the nutritive fluids ; and the propagation 

 of the species. As what is deemed the 

 complexity of animal life increases, we find 

 distinct organs allotted for each of these 

 functions ; thus we have organs of diges- 



