226 
APOSPORY IN PERNS. 
equally unlike what normal sporangia would appear at the same 
stage. I give an enlarged representation of one of the pseudo- 
sori {Plate VI,, Fig. 2), by which it will be seen that they 
consisted of a considerable number of clavate bodies occupying 
the place of sporangia. I expressed my opinion that under 
more favourable circumstances some four or five of these bodies 
would have assumed predominance and become pear-shaped, the 
rest aborting, as in many analogous cases- — an opinion which was 
strengthened by the fact that among the bases of the pear^ 
shaped bodies of 1883 there were numerous thready and 
shrivelled bodies, which were exactly such as w'ould result from 
such a process. 
The outcome of this exhibition was that Dr. Murie, Professor 
Thiselton Dyer, and another, requested me to supply them with 
material for further investigation. I did so, and Professor Dyer 
deputed Prof. F. 0. Bower to examine the matter, with the result 
that my observations were confirmed throughout ; Prof. Bower, 
on December 18, giving his report, and stating that an 
undoubtedly new phenomenon was thereby shewn to exist, viz., 
the reproduction of a fern by sexual action taking place upon prc- 
thalli which had been generated without the mediation of the spore, 
to which phenomenon he gave the term Apospory. Prof. Bower 
upon that occasion demonstrated that the prothalli sprang from 
the stalk of the sporangia, that portion of the sporangium which 
would normally produce the capsule filled with spores being 
either entirely aborted at an early period or partially formed and 
then thrown off. In some cases they appeared to have exhausted 
their energy in endeavouring to produce spores, since in every 
case where they had made a distinct advance in that direction 
they were afterwards aborted altogether. 
This singular fact throws, 1 think, some light upon the 
formation of the pear-shaped bodies of 1883, where w^e may 
assume that the extra stimulus of a specially favourable season 
