1898] BRIEFER ARTICLES 125 
tions are based, excepting Marsilea, was collected in the vicinity of 
Chicago. 
OsMUNDA CINNAMOMEA L. — Rhizomes with strong buds were dug up 
November 11, 1897, the woolly covering was removed, and small parts 
of fertile branches were killed in chrom-acetic acid. The entire 
absence of mitotic figures showed that cell division had ceased. The 
average condition of the sporangia is shown in fg. 7. The sporo- 
genous tissue has reached the spore mother cell stage, but the 
cells are still sharply angular, not yet showing any tendency to 
assume the spherical form which precedes division into tetrads. The 
cytoplasm is dense and not at all vacuolated. None of the nuclei show 
synapsis, but the chromatin is evenly distributed. There are usually 
‘wo or three nucleoli. Some of the nucleoli are cyanophilous and 
others erythrophilous, even in the same nucleus, but on the whole one 
kind or the other predominates in any given sporangium. In both 
kinds there is considerable variation in the intensity of the stain, an 
indication that the nucleoli are undergoing changes. The tapetal cells, 
while rather poor in contents, are not breaking down like the cells 
between the tapetum and the epidermis. 
PS QUADRIFOLIA _L.—JIn the mature sporocarps collected 
€r To, after the leaves had rotted, both microspores and macro- 
mri had nearly reached their full size, but were still uninucleate, ger 
ation under natural conditions not beginning until the next spring. 
oo Apus Spring.—The development is carried further 
arsilea, the prothallium attaining considerable size before the 
Macrospore js shed. 
— 2 aes Poir.—Several stages were studied. Microsporangia 
ih had gs aa January, and the following April are represented 
This vies 4 tespcetively. All are in the spore mother - stage. 
ate i : “ae by the fact that in a section of a sporangium the 
“tettads’ fn oa wthin the tapetum corresponds with the number of 
tapetum is pe € April sporangia. Guignard’s rule that when the 
mother cel] riieng the sporogenous tissue has reached the spore 
§© Is sustained by all the microsporangia which I have 
€Xamin 
iia In October specimens ( fg. 2) the spore mother cells have 
sey nucleoli which are quite uniformly cyanophilous. In the 
aterial ( fig. 3) the nucleoli are very inconspicuous, but 
as the nuclei. resume their growth in the spring ( fig. 4)- 
re shows three nuclei in synapsis, while the other nuclei have 
Teappear 
his figu 
