1888. | BOTANICAL GAZETTE. 267 
course, this process is presumably the reverse of that which 
would take place were the guard cells in their normal posi- 
tion in relation to the surrounding tissues. In fig. 8 a longi- 
tudinal radial section of the stoma is given. Below the 
stoma the usual air-chamber is found. ; 
Scattered singly or in groups of from two to ten within 
the cortex, and also the pith, are found very long sclerenchy- 
matous fibers. They are thick-walled and shining. Their 
length is indefinite, but seems usually to equal that of the in- 
ternodes. These fibers are much more numerous in the cor- 
tex than in the pith. Next within the cortex is found the 
bundle sheath of very delicate walled cells. Within this is 
umstances. 
part ot the 
differences, S I onan oe 
: ‘ ome of the cells are quit e 
With surrounding ones. These long cells are generally oe 
Zontally or spirally banded, and the walls are rathe usual 
'8- 10, sf.). Other cells are shorter, and Be more Or 
"ghar ends of all tracheids. Most fi ie in the 
Ss ‘ j Le Ww 
Pirally banded, and have thinner Wi ngs of all gym 
older wood hav . . di k - ni 
e the characteristic G15 : spi- 
aermous stems, while others have both the at a8 
markings. The pith cells are different” ” 
