22 
After this refreshment the meeting was held, at which Mr. Leipner took 
the chair, and also delivered the first of a series of addresses upon Ferns. 
The subject would be treated in two parts — one to embrace a history of the 
development of the fern, from the spore to the perfect plant ; the other a 
description of the structure of the plant itself. Taking the latter first, the 
speaker made some observations on the stem, the structure of which was 
described and illustrated with diagrams, and with a portion of the stem of a 
tree-fern, particular attention being called to those portions where the speak- 
er's own observations differed from the descriptions usually given in hand- 
books of botany, the result being that the stem was shown to acquire a longitu- 
dinal increase of bulk, and was not during its living state hollow. Ferns 
might be divided into two classes, viz., those having a creeping rhizome, and 
those in which the undeveloped fronds formed a circular crown. These 
latter always had a definite number of fronds to the circle, and the fronds 
were formed simultaneously, or nearly so ; owing to this the number of 
vascular bundles in the stem was also definite. The shape of these bundles 
in the frond was similar to those in the stem, and varied considerably ; 
those in the stems of plants with winged fronds, as in Pteris aquilina, being 
horse-shoe-shaped, and an attempt had been made to classify the genera in 
this way, but had failed in consequence of difference of form. The 
venation of ferns was characterized by continual forkings. The reproduc- 
tion of ferns was accomplished either by budding or by spores. Of the 
budding process there were four divisions. (1). Growing buds formed on 
the upper surface of the fronds, as in Asplenium flaccidum. (2). Growing 
buds from the centre of the racis of a winged frond, as in Woodwardia 
radicans, and in some species of the English genus, Polystichum. (3). 
Resting buds, formed from the racis as in the genus Cysopteris. (4). 
Small tubers produced from the rhizome, which afterwards developed into 
a frond. The true reproduction was, however, by spores, and the varied 
manner in which these were found on the plants had been used to divide 
the order into several sub-orders. In the genera Botrychium and Ophio- 
glossum the thecae were collected into a spike which was shown to be a 
modification of the structure of the frond. In the Polypodiaceae the thecae 
were surrounded, either laterally or vertically, with an elastic ring, an ap- 
pendage which prevented the admission of the Osmundacese into the former 
sub-order. The observations, which were illustrated with a number of dia- 
grams, specimens, and microscopic preparations, will be continued on a 
future occasion. 
