APPENDIX. 
105 
SINGULAR MODE OF REPRODUCTION IN 
ATHYRIUM FIL 1 X-FOEMINA VAR. CLARISSIMA. 
Further Notes on a Singular Mode of Reproduction in 
Athyrium Filix-foemina, var. Clarissima. By Charles T. 
Druery. Communicated by Dr. J. Murie, F.L.S. (Read 
November 20, 1884.) 
AT a meeting of the Linnean Society in June last I had the 
honour of bringing before your notice a record of certain 
phenomena which I had observed during the past winter in 
connection with the reproduction of a form of Athyrium Filix- 
foemina through prothalli, which were not produced from spores, 
but from certain excrescences evolved in their stead upon the 
under surface of the pinnae. The Athyrium in question, which 
was found wild in Devon, had been for many years reputed 
barren, the fructification, which appeared copiously, yielding no 
perfect spores, the result being that after a long period only two 
plants existed, the original plant having permitted but one 
division. In 1883, one of these plants, which had been grown 
under cover, was observed to produce upon the inferior surface of 
the pinnae a large number of curious excrescences, consisting of 
pear-shaped, bulbilloid growths, attached firmly to the frond by 
their thicker extremities, and seated in every case within indusia, 
thus occupying the place of sporangia, to which, however, they 
bore no resemblance whatever. Mr. G. B. Wollaston, whose 
attention was drawn to them by the previous discovery of bulbils 
proper upon other Athyria in the same year, which bulbils also 
occupied the place of sori, was of opinion that they were also 
bulbils. Flowever, on comparing them with the bulbils produced 
on these other Athyria, 1 was struck by the fact that, while in the 
other cases the bulbils were seated in the centre of scales arranged 
shuttlecock fashion around them, in this case indusia were 
present instead, which led me to look upon them as sporoid 
growths of a character essentially different from the bulbils 
common to many Ferns. I consequently laid down a number of 
pinnae, with the result that 1 read before you in June, viz., the 
production of perfect prothalli by the bifurcation of the points 
of the pear-shaped pseudo-bulbils, which prothalli eventually 
developed archegonia and antheridia, and finally yielded plants 
of the same type as the parent. 
At the meeting in June I could do no more than lay the 
consecutive record of my observations before you, since all traces 
of the preliminary stages had vanished when the young plants 
appeared, and these were then too diminutive for their character 
to be determined ; they also afforded no evidence whatever that 
