FABRIC OF PLANTS. 



Intercellular Canals. 



The junction of the cells may be so close, that no 

 interval is perceptible ; but it is often not so, and a space 

 is left, varying in size and form in different plants, 

 This space is termed an intercellular passage 1 , and is 

 always large in fleshy and juicy plants, as nasturtium, 

 and, so long as a plant is alive, is filled with fluid. M. 

 Link describes a larger interval which always runs 

 perpendicularly, while the preceding may run in any 

 direction. The perpendicular sort he terms intercellu- 

 lar ducts 2 . Rudolphi and Mirbel deny the existence 

 of these. 



Perpendicular intervals, called intercellular ducts, shown in the 

 black squares between the cells of swine thistle. 



In these passages Rafn discovered small transparent 

 needle-shaped substances 3 , whose use is not known. 



(1) In Latin, Mentits inter celhiluris. 



(2; In Latin, Ductus inter cellular is. 



(3) In Latin, R'ipfiides. 



