APPENDIX. 
i io 
APOSPORY IN POLYSTICHUM ANGULARE, VAR. 
PULCHERRIMUM, WILLS. 
Extracted from the Linnean Society’s Journal — Botany, vo!. xxii. 
On a new Instance of Apospory in Polystichum angulare, 
var. pulcherrimum, Wills. By Charles T. Druery, F.L.S. 
(Read December 16, 1886.) 
IN December, 1884, and previously, I brought before the notice 
of this Society the results of certain investigations into a mode of 
reproduction in Athyrium Felix-foemina, var. Clarissima, hitherto 
unobserved, and to which Professor F. O. Bower gave the name 
of apospory, the spore being eliminated from the life-cycle of the 
Fern, the prothalli springing direct from the stalks of aborted 
sporangia. This discovery in the variety of Athyrium in question 
was followed by Mr. G. B. Wollaston’s discovery of a kindred 
phenomenon in an abnormal form of Polystichum angulare, var. 
pulcherrimum, Padley, in which plant, however, it is developed 
in an altogether different manner, the prothalli being produced in 
this case by simple extension and dilatation of the growing tips of 
the pinnules, so that not only the spore, but the entire sorus is 
excluded from the normal cycle of existence. 
The particular specimen of Polystichum angulare, in which 
this phenomenon was remarked, was found many years pre- 
viously growing wild in North Devon, since which time it had 
constantly produced its characteristic expansions of the pinnule- 
tips, which, however, were regarded at first as a minute form of 
that cresting common to so many abnormal forms of Ferns, and 
consequently their true character as prothalli proper remained 
for a long time unsuspected. 
One of the peculiar characteristics of this Fern is a marked 
elongation of all the lower divisions of the pinna?, i.e., pinnules, the 
upper ones retaining nearly or quite their normal outline ; and as 
it was mainly upon these attenuated divisions that the prothalli 
were formed, the points running out into threads at the ends 
of which the prothalli appeared, it struck me that as these 
attenuated pinns were not confined to this individual Polysti- 
chum, others presenting the same peculiarity might develop the 
rest of the phenomena under suitable treatment. I consequently 
applied to Colonel Jones, of Clifton, for whose aid throughout 
these investigations I cannot too strongly express my thanks, and 
was duly furnished with a young plant, of the form known as 
P. angulare var. pulcherrimum, Wills, found by the late Dr. 
Wills, in Dorsetshire, some years ago. This form, which, it will 
be noted, was found some seventy or eighty miles distant from 
