WITH ANIMAL PHYSIOLOGY. Ill 



parison, however, between the two, is so inter- 

 esting and instructive, that a few words may be 

 well bestowed upon the subject. 



The whole range of functions both of animals 

 and plants, that is to say as far as nutrition and 

 reproduction are concerned, affords ample illus- 

 trations of the near approach to similarity in the 

 two kingdoms a few examples of each may 

 prove the truth of this assertion, while the dif- 

 ference will also in general be equally percep- 

 tible. In the entire course of that function by 

 which the individual is nourished, the main 

 point holds good in both cases ; i. e. that mat- 

 ter fitted for its food is taken into the system 

 by the appointed organs, thence conveyed through 

 the necessary channels, assimilated and con- 

 verted into the requisite substance for continu- 

 ing and replenishing the tissue of the body, and 

 furnishing the needful secretions, while such as 

 is unavailing to any of these purposes, is ex- 

 creted. In the plant, however, the juices are 

 not conveyed to a single receptacle, there to be 

 elaborated, but, according to the process de- 

 tailed in the foregoing pages, are gradually in 

 their progress converted from the crude into 

 the nutritive sap. The circulation of this sap, 

 and the power of the glands to convert it into 

 peculiar secretions, suggests immediately to the 



