20 FERNS OF GREAT BRITAIN. 



2. PiLULARiA (Pill-wort). — Capsules globular, 4-celled, 

 each cell containing two different kinds of bodies. Name 

 pilula, a little pUl, which its fructification resembles. 



Order IV. EQUISETACEtE.— HORSETAILS. 



These are leafless, flowerless, sometimes aquatic plants, 

 with a hollow, subterranean, creeping stem, and hoUow 

 stems marked with lines, and sheathed at the bases of the 

 joints. The fructification is produced in terminal spikes 

 or catkins, either placed on the stem of the branched 

 frond, or on a separate simple frond of earlier growth. 



1. Eqtjisetum (Horse-tail). — /S'^e«2s jointed and tubu- 

 lar, fertile ones mostly unbranched and succulent ; barren 

 stems with whorled branches ; fructification in a catkin. 

 Name from equus, a horse, and seta, a hair, because 

 some of the barren fronds resemble the tail of a horse. 



1. PoLYPoDiuM (Polypody). 



1. P- vulgar e (Common Polypody) .^-i'Vo;^!^* deeply 

 pinnatifid ; the segments oblong, and tapering or rounded 

 at the end, the upper ones generally smaller. This 

 is one of the commonest of our Ferns, and one which is 

 of easy recognition. It is abundant on all parts of our 

 island, now hanging down from the gnarled branch or 

 sturdy trunk of the old oak, now growing in large 

 clumps on the hedgebank, and forming a good fore- 

 ground for the artist's sketch ; while sometimes it may 

 be seen waving its bright green leaves above the cottage 



