APPENDIX. 
I T I 
Mr. Padley’s station, moreover differs markedly in general 
character, so that no doubt can reasonably be entertained of its 
distinct origin ; the characteristic prothalloid extensions had also 
never been remarked upon it. 
On receipt of the plant early in the present year (1886), 1 
at once placed it in a closed Todea frame, with the result that as 
soon as the fronds attained the length of some six inches or so I 
was delighted to find the tips of the pinnules running out and 
dilating into prothalli in profusion, until the pinnae were absolutely 
fringed with them, precisely in the same manner as in Padley’s 
form. Later in the season, however, the close treatment dis- 
agreed with the plant, and on removal from the frame to a cool 
fernery the prothalli dried up and perished ; fortunately, how- 
ever, not before Professor Bower was able to inspect the plant and 
obtain material for further investigation. It seems highly pro- 
bable, from the rapid disappearance of the prothalli, in this case 
under nearly normal conditions, that they would not be developed 
under ordinary circumstances to an extent likely to attract 
observation. 
So far, the phenomena observed had been precisely similar to 
those noticed in Padley’s form ; but upon further close examina- 
tion of the fronds 1 was struck by the existence of several 
hydraform bodies, clearly visible to the naked eye, which 
appeared to be attached to the upper surface of the pinnules well 
within the margin, and in this respect, as well as in their shape, 
entirely different from the prothalliform point-extensions. 
On examining several of these under the microscope, I found 
their distinct character emphasised by the fact that they were in 
every case produced at the ends of excurrent veinlets protruding 
from the surface of the pinnules, well within the margin, and 
thickening at the distance of about one-twentieth of an inch into 
a pear-shaped body, from which radiated in all directions numerous 
root-like hairs. The brown and shrivelled condition of these 
bodies led me to the belief that it was essential to their full 
development, whatever that might be, that they should at an early 
stage find some suitable nidus whence the hairs, assuming them to 
be root-hairs, might obtain the needful elements for growth. 
After a long search I was fortunate enough to find one of these 
bodies in a young state, the pear-shaped head only being formed, 
and the hairs just beginning to develop. 1 at once removed the 
plant into a large shallow pan and pegged down the frond so that 
the excrescence was brought into very close proximity to the soil. 
This was on September 5, when it presented the appearance 
shown in figs. 1 and 2. On September 10 I observed that 
the root-hairs had much developed, radiating stiffly in all 
directions without any apparent bias towards the soil (fig. 3). 
