I0o BOTANICAL GAZETTE [JANUARY 
A convenient classification of types of apogamous development 
has been presented by FARMER and Dicpy (2), who begin their 
classification by distinguishing between premeiotic and postmeiotic 
apogamy. All the prothallia described in this paper were raised 
from spores, and accordingly the cases would be postmeiotic. ‘The 
only case of obligate apogamy was found in a prothallium of 
Dicksonia squarrosa (Forst.) Sw. This prothallium had numerous 
antheridia and, although it was sufficiently large and had a well 
developed cushion, it had no archegonia. It produced two apoga- 
mous buds on the ventral side in the region where the archegonia 
usually appear (figs. 1, 2, 3). Behind one of the buds was a region 
where the thallus had thickened considerably and the outer cells 
had died. The presence of the characteristic cyatheoid antheridia 
makes it certain that this is not a polypod prothallium. Many 
prothallia of D. squarrosa showed the development of archegonial 
projections, such as Hem (5) found on the prothallia of Doodia 
caudata and LANG found associated with apogamy in the species 
which he studied. Such projections are shown in figs. 4 and 5. 
D. squarrosa sometimes produced embryos as the result of fertiliza- 
tion, but these were not found on prothallia which had archegonial 
projections. 
Cyathea muricata Wild. (Alsophila muricata Desv.) furnished 
the case shown in fig.9. This may be the apogamous development 
of the oosphere, but it is quite as likely that it is the apogamous 
development of the ventral cell. Adjoining sections show that the 
archegonium had not opened. A nutritive region had begun to 
develop around the embryo. It will be noted that the shape and 
sequence of cell divisions are not the same as in the usual type of 
embryo. 
In Cyathea Tussacii Desv. there were several cases of a peculiar 
behavior of the central cell. The first division does not cut off 
the primary neck cell, but instead cuts off a lateral cell (fig. 7). 
The central cell develops in the usual manner, while the lateral 
cell develops such structures as are seen in figs. 6 and 8. Such 
a division in the central cell was found also in Dicksonia squarrosa 
and a single case occurred in Cibotiwm Schiedei Schlecht. and Cham. 
Cyathea Tussacii and Cibotium Schiedeit both produced archegonial 
