ISOETES. 



5/5 



The spores often totally escape, are membranous hyaline, 

 with triangular inner face, and a tendency to evolution on the 

 dorsum ; after making their escape, they assume entirely a 

 spherical form, precisely like, but much less in size than the 

 original parent cell, before the tendency to devision, less solid 

 looking. In the spores there are still some remains of gru- 

 mous granules, or they are quite empty. 



The nucelli, green spots are the first to appear, then the tri- 

 angular subdivisions. 



Very early the cells are solid, septa opaque from air, the rest 

 lax, more especially towards centre, with a brownish pointed 

 disk ; parent cells even more decidedly brownish. One or two 

 are visible only in each, on a thin transverse section ; it is along 

 the outer that these are developed from below upwards ; for 

 while it is divided below by septa, it is below a subsigmoid 

 shaped mass of dense brown reproductive tissue, in the sep- 

 tous part however the parent cells are already distinct. 



The septa are most developed along the mesial line, and 

 are developed from back to front. 



There is little distinction of cuticle. 



The parent cells are not free now ; they are attached to 

 the surrounding cellular tissue. Pressure occasions them to 

 discharge a grumous granular matter, occasionally they have 

 the appearance of internal sub-division. 



All sorts of formation may be seen, in one instance, five-form 

 spores may be distinguished, as well as quaternary, while in 

 some there will be no septa. 



The next stage is the formation of the partitions between 

 the nuclei, or rather ; the contraction of the grume until the 

 hyaline cell is left alone on the circumference.] 



PI. CXV1. (Upper division.) 



1. Sporula different faces, considerably advanced 



2. Quaternary state one younger. 



3. Ripe fruit, natural size. 



3a. Transverse section of the same. 



