BRIEFER ARTICLES 
APOGAMY IN PHEGOPTERIS POLYPODIOIDES FEE, 
OSMUNDA CINNAMOMEA L., O. 
CLAYTONIANA L. 
Apogamous embryos developed on prothallia of Phegopteris poly- 
podtoides Fee, Osmunda cinnamomea L., and O. Claytoniana L. in cultures 
on Prantl’s and Knop’s full solutions and certain modifications of the 
Prantl’s solution. About 6 months after the spores had been sown, the 
first cases of apogamy were observed in cultures of Phegopteris poly- 
podioides on Prantl’s solution with NH, NO, omitted. The spores from 
which the prothallia developed had been collected during the summer 
from a plant growing on a lawn in Ithaca, New York. The plant did 
not appear in a normal, healthy condition, doubtless owing to the 
unfavorable conditions under which it was growing. After the spores 
were sown upon the nutrient solutions, the cultures were placed before 
an east window, where the conditions of light and temperature were 
approximately the same for all. Once each week the prothallia were 
transferred to fresh nutrient solutions. 
The prothallia, upon which the apogamous embryos developed, were 
heart-shaped and developed archegonia but no antheridia. The apoga- 
mous embryo in most cases originated as a slight swelling of the arch- 
egonial cushion, either on the dorsal or ventral side, at some point near 
the notch or at the center of the cushion. This swelling gradually 
increased until a dome-shaped cellular mass was formed, from which 
the apogamous embryo developed. The parts of the embryo usually 
appeared in the following order: the leaf or leaves, root, and stem. 
However, in one case a root appeared before any other member. No foot 
was formed. In some cases, beside leaves, proliferations, either filamen- 
tous or slightly expanded at the apices, developed from the cellular mass. 
October 7, 1916, two series of cultures on the Prantl’s and Knop’s full 
nutrient solutions and modifications of the Prantl’s solution were made. 
Fresh spores from the same plant at Ithaca, New York, as well as spores 
of the same species secured through the kindness of Dr. A. H. GRAVES 
from Brooklin, Maine, were used. As soon as the spores were sown upon 
the nutrient solutions, one series was placed in the greenhouse in bright 
light, while the other series was kept in the laboratory before an east 
window. The prothallia were not transferred to fresh solutions, but 
435] [Botanical Gazette, vol. 64 
