APPENDIX. 
103 
usual root-hairs developing under the prothalli. On March 17 
several of these prothalli were examined microscopically, both by 
myself and by the Rev. Mr. Aubrey, of Salisbury (to whom 1 
am indebted for aid in observing the final stages of growth), and 
well-developed archegonia were found in the usual place and 
number, but so far neither of us was able to detect antheridia. 
Early in May, however, 1 succeeded in finding a single 
antheridium ; and it is manifest that many others must have been 
present on the prothalli not examined, as on May 21 the' final 
stage was reached, small fronds being visible in several cases, 
projecting from the bifurcation of the prothallus, and evidently, 
therefore, produced from the archegonia by the ordinary sexual 
mode of reproduction ; though the prothalli, as has been shown, 
had developed from growths that differed widely from spores in 
their form, their size, persistent adherence to the pinnae, their 
production of root-hairs from their surface, and, finally, in the 
development of the prothallus from their apices by simple 
extension of growth. 
Lest it might be assumed that these prothalli may after all 
have resulted from true spores scattered amongst the excrescences 
described, it should be borne in mind — first, that no spores or 
spore-cases could be distinguished when the pinnae were laid 
down ; secondly, that all attempts to raise this Fern from spores 
have failed ; and, finally, that the entire development of the 
prothallus from the pointed tip of the pear-shaped pseudo-bulb — 
its dilatation, bifurcation, and gradual assumption of the true 
prothallus form — has been carefully watched and noted step by 
step, not merely in one case, but in many, in all of which the 
prothallus was evolved precisely in the same way. 
Where, as in this case, the whole phenomenon is new to the 
observer, many points of interest are apt to be overlooked, their 
importance being unknown until too late. Another season’s growth 
may therefore confidently be expected to throw more light upon 
this development, and especially in relation to the first appearance 
of the pseudo-bulbils themselves, which only came under close 
observation when already of considerable size. 
In framing this account of the occurrence, I have confined 
myself as strictly as possible to a simple, and I hope clear, 
record of the phenomena observed during the various stages 
of growth of the abnormal sporoid excrescences under obser- 
vation. In conclusion, however, 1 may be permitted to point 
out, in connection with such phenomena, that, so far as formal 
records are concerned, the family of Athyria has hitherto 
been remarkable for the non-proliferous cha meter of the fronds, 
which, considering, first, its near relation to the Asplenia, so 
many of which are profusely proliferous, and, secondly, the 
