SCOLOPENDRIUM VULGARE 



225 



and a heavy - headed grandiceps, with large bunch crests ; the 

 fronds indeed being a collection of such, and connecting bare 

 stalks. The latter only grows about two feet high, the former four 

 or five. 



Polydactyla (Fig. 263), in which the terminals of the sub- 

 divisions are branched into numerous slender points. 



Revolvens. — Found at Windermere and near Chepstow by the 

 writer ; a robust, handsome form, with fronds convexly curved 

 and tips and side divisions terminating spirally. 



SCOLOPENDRIUM VULGARE (The Common 

 Hartstongue) 

 (Plate XXXV) 



With the exception of the little Adder's-tongue Fern (Ophio- 

 glossum vulgatum), the Hartstongue Fern is the only British 

 species in which normally the fronds are quite undivided. In 

 the Hartstongue they consist of a stalk of about one-third of the 

 whole length, surmounted by a long, leafy portion, commencing 

 with two rounded lobes of a semi-heart shape, whence the frond 

 continues with smooth parallel edges for some distance, finally 

 narrowing and terminating in a bluntish point. In robust speci- 

 mens the fronds may be between 

 two and three feet in length by 

 three or four inches in width. 

 The Fern is perfectly evergreen, 

 and its fronds are of a dark, 

 shining green and fleshy texture. 

 Its fructification is peculiar, as is 

 shown by Fig. 264, consisting of 

 two rows, arranged herring-bone 

 fashion on each side the midrib, of 

 long, sausage - shaped masses of 

 capsules, each mass on close ex- 

 amination being found to consist 

 of two lines, distinct when im- 

 mature, but confluent when ripe. 

 Each line is exactly of the Spleen- 

 wort type, and has the same translucent skin-like cover or indusium, 

 but in Scolopendrium these covers are situated on the outer edge of 

 each pair, and turn inwards towards each other, so that in the early 

 stages of growth their opposed free edges meet, but are subsequently 

 forced asunder as spore growth proceeds. This peculiarity dis- 

 tinguishes the genus Scolopendrium from the Asplenia, to which, 

 however, it is very closely allied, so closely, indeed, that hybridiza- 

 tion has been effected (S. vulgarexAsp. Cekrach) by Mr. E. J. 



Fig. 264. Scolopendrium vulgare 

 (part of frond). 



