STRUCTURE] 



ENDOGENS. 



221 



will be referred to hereafter in the explanation to be given of 

 Schleiden's peculiar views of the structure of stems. Without 

 plates it would be of little use to introduce these descriptions, 

 nor, in the absence of some good theory, which will connect 

 such examples with some general law, does it appear neces- 

 sary to the purposes of the student that they should be 

 particularised. 



2. Of the Endogenous Structure. 



fig. 43. 



Plants of an arborescent habit having this structure 

 being almost exclusively extra-European, and most of them 

 natives only of the tropics, botanists have had much fewer 



fiff. 44. 



opportunities of examining them, and, consequently, our 

 knowledge concerning them is more limited. Nevertheless, 



