FILICES. 



1037 



obscurely crenate. Fructification form- 

 ing a more or less compound panicle at 

 the top of the frond, usually bipinnate, 

 each spike-like branch representing a 

 segment of the frond. 



In moist or boggy places, in west- 

 ern, central, and some parts of south- 

 ern and south-eastern Europe, extend- 

 ing northwards to southern Scandi- 

 navia ; also in central Asia, North and 

 South America, and southern Africa. 

 In Britain, chiefly in the western coun- 

 ties of England and Scotland, in 

 Wales, and Ireland, apparently very 

 local in other parts of England, and 

 entirely absent from several counties. 

 Fr. end of summer, or autumn. 



Fig. 1260. 



IV. POLYPODY. POLYPODIUM. 



Fronds (in the British species) either pinnate or ternately divided, 

 with the branches pinnate. Spore-cases minute, collected in circular 

 clusters or sori on the under side of the segments, without any indu- 

 sium or involucre ; each spore-case (as in all the following genera) en- 

 circled by an elastic jointed ring, and bursting irregularly on one side, 

 having then, under a microscope, the appearance of a little helmet. 



A large genus, widely distributed over the globe, only differing from 

 Aspidium in the absence of any indusium or membrane covering the 

 sori even when young. For the Table of Species, see the Generic 

 Table above, p. 1033, n. 13. 



1. Common Polypody. Polypodium vulgare, Linn. 

 (Fig. 1261.) 



(Eng. Bot. t. 1149.) 



Hootstock thick, woody, and creeping. Fronds about 6 inches to 

 a foot high, of a firm consistence, without any scales on their stalk, 

 broadly oblong-lanceolate or somewhat ovate in their general outline, 



