436 
In Cyathea brunonis and Citbotium chamissot of the Cyatheacee 
which I have examined, divisions strictly homologous with those 
pointed put in the Polypodiacez are found. The true annulus, 
i. ¢., that portion which functions as the spring, extends from the 
lower anterior angle of the sporangium, backward by the side of 
the stalk, up the dorsum and over the vertex to the anterior up- 
per angle. A series of four to six lip cells similar in appearance 
to, but smaller than those of the true annulus, occupies the mid- 
dle of the front. Between two of these the line of cleavage occurs. 
An upper and lower connective, each consisting of two or three 
cells exactly like those of the lateral walls of the sporangium, in- 
terrupts the so-called “complete annulus.” Sporangia of both 
these species, which had lain in the herbarium over thirty years, 
when moistened with water and then dried, or treated with gly- 
cerine to extract the water from the cells of the annulus, opened 
promptly by the everting of the part of the annulus here designated 
as the true annulus. The spring also occurred with as much snap 
seemingly as might have taken place at the time of the dehis- 
cence of the sporangium. The entire proceeding could easily be 
watched under the high power of the microscope, and it was easy 
to see which part functioned as the spring and which part was 
passive. 
In Hymenophyllum demissum and H. ciliatum the true annulus 
occupies a greater portion of the circumference of the sporangium 
than in the Cyatheacez, but it is not complete. The short stalk 
is attached nearly perpendicular to the sporangium by the side of 
one end of the annulus. Narrow elongated lip cells are present 
joined to the annulus by two small connectives, and in dehiscence 
the sporangium is divided into halves. 
In the Gleicheniaceze as shown by Gleichenia emarginata the 
same divisions are present, but the connectives are quite large and 
prominent, as shown when a longitudinal section of the annulus is 
made. 
In Schizea pusilla and Aneimia Phyllitidis of the Schizeacee® 
elongated lip cells and small connectives are present, and the true 
annulus when seen in side view and in section stands out quite 
prominently from the other parts of ones ring of cells at the pean 
_ of the ovate sporangium. 
