MALE FERN AND ITS RELATIVES 63 



is very pronounced. The covering is so thick 

 on the underside that it is rather difficult 

 to discover the son. These have the same 

 curious divided indusia to be observed in the 

 Alpine Woodsia. 



The Oblong Woodsia is a very rare Fern, only 

 to be found in mountainous districts. It has 

 been reported from a few localities in England 

 and also occurs in Scotland, usually in almost 

 inaccessible places. The fronds die down in 

 the winter and break away from the Astern just 

 at the crown of the root -stock. 



Cystopteris fragilis. The generic name of this 

 Fern is formed of the two Greek words kystos, 

 " a bladder." and pteris, " a fern." The 

 specific name is, of course, a Latin word which 

 means " easily broken." The Brittle Bladder 

 Fern. 



This is one of the most beautiful of all our 

 native Ferns. From a tufted root-stock which is 

 clad with pale brown scales the fronds arise ; 

 these are about six or eight inches in length and 

 are lanceolate in outline. This Fern has a habit 

 of spreading in such a way, that each plant may 

 have several of the tufted crowns from each of 

 which arise a cluster of fronds. These are 

 sometimes once, and on other occasions, twice 

 pinnate. The pinnae are about an inch in length, 

 and where there are pinnules these are toothed. 



We shall find the sori on veins which run from 

 the mid-vein of the pinnules. The spore patches 

 are rounded and are covered with a curious in- 

 dusium, with an inflated appearance towards the 

 centre. It is from the resemblance of this 

 indusium to a bladder that the plant has received 

 its popular name. With the disappearance of 

 the indusia the sori tend to spread over the whole 

 surface of the back of the frond. The general 



