H 



BRITISH FERNS 



of the Fern, we may now proceed to consider the normal life cycle 

 peculiar to Ferns generally as distinct from that of flowering plants. 

 In the latter it is much shorter as regards the several steps or stages 

 involved. (Starting with the seed as sown, on reaching a congenial 

 spot where there is sufficient warmth and moisture to induce 

 germination, its husk swells, bursts, and emits first a root which 

 enters the soil, and then a primary leaf or two leaves, according as 

 it belongs to one or other of the two great plant divisions of Mono- 

 cotyledons and 

 r~ 1 Dicotyledons, at the 



base or in the angle 

 of which there is a 

 bud. This bud pro- 

 duces more leaves, 

 and without further 

 circumlocution the 

 young plant is pro- 

 duced. With the 

 spore, on the other 

 hand, when sown 

 under congenial 

 conditions , although 

 it bursts its husk 

 and produces an 

 outgrowth, this out- 

 growth does not 

 consist of a root 

 proper and an as- 

 I sociated leaf or 

 leaves, but forms 

 I a small green semi- 

 translucent scale, 

 j more or less heart- 

 j shaped, which is 

 attached somewhat 

 closely to the soil 



Fig. 5. — Development of young Fern. 



by means of a number of root-hairs. This scale starts with a short 

 row of cells from which protrude the first few root-hairs as the 

 row lengthens by cell fissure and multiplication ; but very soon 

 the cells multiply laterally as well, until the heart-shape in question 

 is visible, which then increases in size until it is perhaps a quarter 

 of an inch in diameter, the two rounded lobes being fairly free of 

 the soil, while the abundant root-hairs are clustered at the other 

 end. At this stage, if this scale or prothallus be detached and its 

 under-side examined with a good lens, it will be seen that among 

 the root-hairs there are a number of rounded, pimple-like projec- 

 tions irregularly scattered, and that close to the indentation of the 



