1898-99] 499 



series or in a kind of crowned whorl. In the rhizome 

 stem the fronds are more scattered, and are developed 

 from the sides of the axis of growth which is in advance 

 of the last formed fronds. The leaf-like organs are called 

 tronds ; they differ from the leaf of flowering plants in 

 that it bears on its surface]the parts known as the fructifications, 

 which the true leaf does not. When the fronds become fully 

 developed, two parts, the stipes and the lamina are dis- 

 tinguishable; the stipes in the stalk, and the lamina the 

 leafy portion. This part affords great variety in the mode in 

 which it is divided, fronds are undivided, others divided into a 

 great variety of forms. Fern fronds are traversed by ribs or 

 fibres, which serve to give them their elasticity ; these are the 

 veins which are given off from the midrib, and, as a rule, are 

 furcate. It is probably to this furcate growth that we are 

 indebted for the endless varieties of British ferns. The veins 

 are developed faster than the herbaceous portion, and so the 

 fronds branch and tassel. The reproductive organs consist of 

 spores enclosed in cases, which are collected into groups called 

 sori, and in most British ferns are borne on the back of the 

 fronds. From the germinating spore arises a leafy expansion 

 called a prothallium, which gives off delicate root fibres from 

 the under surface. Scattered among these fibres are several 

 minute microscopical cellular bodies which are called antheridia 

 and archegonia, which correspond with and perform the 

 functions of stamens and pistil in flowering plants. The 

 number of ferns known to botanists number about 3,000. Of 

 these about 43 are natives of the British Isles, and about the 

 half are to be found in the Counties of Antrim and Down. 

 There seems to be no limit to the varieties which may be found 

 or raised from spores. By careful search these variations are 

 to be found in almost all parts of the country, and the 

 possibility of finding new foims gives a stimulus, and the 

 exertion of a long walk raises the enthusiasm of the fern 

 collector in a way that is not done by any other class of plants. 

 A description of the different genera and species was then 



