APOGAMY IN THE CYATHEACEAE 
Atma G. STOKEY 
(WITH TEN FIGURES) 
Since the discovery of apogamy in Pteris cretica by FARLow (3) 
in 1874, it has been observed in about 15 genera and 30 species of 
the Polypodiaceae. There are records of its occurrence in 3 other 
families of the Filicales, namely, the Osmundaceae, the Hymeno- 
phyllaceae, and the Marsiliaceae. It has been reported by SADE- 
BECK (9) in Todea africana, by Le1tcEB (7) in Osmunda regalis, 
by STANGE (12) in Todea rivularis and T. pellucida, by BowER (1) 
in Trichomanes alatum, by WoRoNIN (14) in Trichomanes Krausii, 
and by SHAw (11) and STRASBURGER (13) in Marsilia. 
For several years I have been making a study of the prothallia 
of the Cyatheaceae, most of the results of which will appear in a 
later paper. I have had under cultivation 13 species belonging to 
5 of the 7 genera. The species studied include 6 species of Alsophila, 
1 of Hemitelia, 2 of Cyathea, 2 of Dicksonia, and 2 of Cibotium. 
I am indebted to Dr. J. M. GREENMAN for the determination of all 
the species with the exception of Alsophila Cooperi F. Muell., 
which was obtained from the greenhouses of Harvard University, 
and Cyathea muricata Wild. (Alsophila muricata Desv.), obtained 
from the New York Botanical Garden. 
In order to obtain pure cultures it was found necessary to take 
.Measures to remove foreign spores from material obtained from 
greenhouses where other ferns were growing. The leaves, which 
were collected before the sporangia had begun to open, were washed 
in running water and brushed rather vigorously while in the water. 
They were dried on sterilized glass plates and the spores which were 
collected were sowed on various culture media. Cultures from 
material handled in this way contain few if any foreign prothallia. 
It is not difficult to tell by the appearance of a culture whether or 
not there are any foreign prothallia present, owing to differences in 
the rate of development and in the general habit of the prothallia 
of different species. It is fairly easy to distinguish between the 
97] [Botanical Gazette, vol. 65 
