and Helminthostachys zeylanica , 31 
cell Into ovum and ventral canal-cell been observed, though 
analogy suggests that it will be found to take place. 
The segmentation of the ovum has also not been traced, 
but embryos were present on a few of the prothalli. They 
were all of about the same age and presented the appearance 
represented in Fig. 28, the embryo being conspicuous as 
a globular projectioii from the side of a branch of the pro- 
thallus. Up to this stage the embryo is completely enclosed 
by the tissues of the gametophyte and surmounted by the 
brown archegonial neck. These embryos were rather old to 
do more than indicate the order of segmentation, and too 
young to make the delimitation of the primary members of 
the young plant certain. A median vertical section (Fig. 29) 
shows the main structural features most clearly. The whole 
of the lower portion is evidently to be regarded as foot ; the 
smaller upper portion consisted of cells with more abundant 
contents, but the position of the primary organs could not 
be determined in it. The first wall separating these epibasal 
and hypobasal halves can be clearly traced and, as a series of 
transverse sections through another embryo showed, the 
quadrant and octant walls followed in each of these halves. 
The resemblance of these embryos to one stage of the embryo 
of Botrychium virginianum , which will be evident on com- 
paring Fig. 29 with Fig. 4 6 of Jeffrey’s paper on the latter 
plant, makes it probable that the earlier and later stages will 
also be found similar in the two genera. 
Helminthostachys zeylanica. 
The prothallus of Helminthostachys was looked for in 
a number of localities in Ceylon and the Malay Peninsula. 
The sporophyte Is found growing under very various con- 
ditions in its different habitats. In native compounds under 
Coco-nut palms It grows in rather dry soil, owing its success 
and its spread, so far as could be seen, to Its power of 
continued growth and to vegetative multiplication. The same 
conditions appear to obtain In the Botanic Gardens at 
