CHAP, i.] TISSUES AND MECHANISMS OF DIGESTION. 423 



whole process, namely the transference through the epithelium 

 cell from the inside of the canal to the lymph-spar*- <f tin- villus. 

 And we may perhaps be inclined still to regard the second step 

 the transference from the lymph-space to the ltlcod stream as 

 more strictly an act of diffusion. But the considerations which 

 we urged ( 236) in regard to translation from the blood vessel 

 to the lymph-space may also be applied to the reverse current ; 

 we may look upon this as something much much complex than, 

 and so different from, ordinary physical diffusion. 



