442 BOTANICAL GAZETTE [ DECEMBER 
In from four to ten hours after the sorus breaks the cortical 
tissues the teleutospores attain full size. By this time the gelat- 
inous membrane has mostly disappeared, and consequently the 
contents and septum separating each teleutospore is plainly 
apparent. 
The teleutospores are arranged in rows of from two to four, 
one above the other. They do not separate, however, from each 
other, and it is with some difficulty that they are removed from 
their attachment in the sorus. When fully mature the compound 
teleutospores vary in length from 75 to 150m and in diameter 
from 18 to 30p. 
The spores begin to germinate as soon as mature, the process 
taking place only in water or saturated air. The first evidence 
of germination is a small protuberance, which may appear at the 
apex or at any of the septa. Usually the topmost cell germinates 
first and the others follow in the order of their arrangement 
(fig. 14). The protuberance rapidly elongates into a tube, 
which may grow to a length several times that of the compound 
spore, or may remain quite short. The length, however, depends 
largely on the amount of moisture present, the tube attaining 
its greatest length if the spore is in water and its shortest if in 
moist air. The contents of the spore flow out into the tube, the 
greater portion being near the tip and the rest more or less In 
groups throughout its entire length. The vacuoles in the cell 
flow out with the contents and may usually be found at the uppet 
extremity of the tube. 
When the tube attains its full length, this, as already indi- 
cated, depending in large part on the amount of moisture pres 
ent, it begins to swell at the tip (fig. 75). The swelling rap- 
idly increases in size and at the same time the walls directly 
below it become more or less constricted. At this point a sep 
tum is formed, this process usually lasting not more than twenty- 
five or thirty minutes, The body thus cut off by the septum 6 
the sporidium, which now begins to increase in size and assumes 
various shapes. Occasionally the sporidium will send out 4 
germ tube while still attached to the supporting promycelium. 
