APOSPORY IN FERNS. 
22B 
or absorbed. Eventually all the tips of the flask-shaped bulbils 
assumed the form of perfect prothalli of the usual size and shape, 
the pseiidobulbils themselves being absorbed and disappearing, and 
the usual root-hairs developing under the prothalli. On March 17 
several of these prothalli were examined microscopically, both by 
myself and by the Eev. Mr. Aubrey, of Salisbury (to whom I am 
indebted for aid in observing the final stages of growth), and 
well-developed archego nia were found in the usual place and number, 
but so far neither of us was able to detect antheridia. Early in 
May, however, I 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, 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 pseudobulb — 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 in the 
same way precisely.” 
“ 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 
