474 BOTANICAL GAZETTE [DECEMBER 
According to my own observations, the process of the formation 
of the spore coats does not agree with the account of FAuULL (:05) 
Fig. 13 shows a young spore which has grown somewhat beyond 
those found in figs. 12a-12c. The limiting membrane is not per- 
ceptibly thickened, showing in sections as an even unbroken line. 
Just inside this membrane, however, the endospore is seen to be but 
slightly differentiated from the sporeplasm, being much less vacuo- 
lated but more hyaline and granular. A more or less distinct bound- 
ary is present between the endospore and the sporeplasm. Exactly 
how the endospore is formed I am at present unable to state, unless it 
is laid down by the original plasma membrane, which has gradually 
withdrawn, secreting the substance of the spore coats as it recedes. 
Finally, the endospore becomes still more granular and hyaline 
as the spore develops (fig. 14). The outermost portion of the 
hyaline granular area constitutes the éxospore. In fig. 14, which is 
not so highly magnified as jig. 13, the central portion of the spore- 
plasm is highly vacuolated. The nucleus of the spore lies in the 
center of this mass of protoplasm. The irregularities on the exo- 
spore may be due to fixation. Lines are developed on the surface 
of the spore, finally producing an irregularly branched system of 
elevations and ridges much like that found on the spores Ascobolus. 
Fig. 15 represents a mature spore. The two germinal pores, one at 
either end, are present, passing through the spore coats. ‘The mature 
endospore is very granular and highly refractive. The inner proto- 
plasm, bounded by the plasma membrane, is still uninucleate but 
densely granular. Smaller vacuoles have entirely disappeared. In 
some mature spores two large spherical oil drops are present, one at 
either side of the nucleus, but not regularly so. Fig. 15 is typical. 
As the asci dry out, the walls become thickened and hyaline. 
Fig. 16 shows the upper portion of a nearly mature ascus, at the 
apex of which is the cap or operculum in the process of formation. 
A thickened ring in the ascus wall is formed below the operculum. 
The mature spores are probably discharged through this terminal 
pore by the turgor of the ascus and the lateral pressure of other asci 
and paraphyses. Although several attempts were made to germinate 
these spores in various sorts of media, I have thus far been unsuccess- 
ful. Perhaps it may be necessary for them to pass through an ali- 
