62 WAYSIDE AND WOODLAND FERNS. 



Snovvdon specimens. They vary from six to eighteen inches in 

 length, with a very short scale-clad stipes, and in form they 

 are a very slender oblong, the lateral outlines being almost 

 parallel, owing to the uniformity in length of all the pinnae 

 excepting a few at each extremity. If the thick leathery pinnae 

 were more symmetrical they might be described as narrow-egg- 

 shaped, but the upper margin is concave and the lower convex, 

 whilst the base has an ear-like lobe projecting on the upper 

 margin. These ears are more noticeable when the back of the 

 frond is in view, as the lower edge of one pinna usually overlaps 

 and hides the ear of the pinna next below it. The margins are 

 also beset with long teeth that end in spine-like hairs. The 

 pinnae have a dark-green, hard and slightly polished surface, 

 but are pale and dull underneath. It is not much subject to 

 variation except in point of size. One variety (Jjulbiferum) is 

 worthy of note as producing bulbils from the base of the lower 

 pinnae. (Plates 56, 58, 66.) 



The sori are produced only on the upper pinnae of the frond, 

 forming one or more rows on each side of the scaly rib of the 

 pinna. They appear from June to August. 



The Holly-fern is a distinctly northern species. The photo- 

 graph here reproduced (Plate 56) is from probably one of its most 

 southern examples, growing at an elevation of about 2500 feet 

 on the rugged escarpment of Crib Goch, one of the spurs of 

 Snowdon. It occurs very sparingly in several spots similarly 

 difficult of access in the same part of Carnarvonshire. Then its 

 next stations are in West Yorks, Durham, and Westmoreland 

 round the lakes. In Scotland, from Stirling to Caithness, it is 

 more abundant, and the specimens attain a larger size. In the 

 Highlands it has been found up to 3200 feet. It is rare in 

 Ireland, where it has been reported from Donegal, Tyrone, 

 Leitrim, Sligo, Meath, and Kerry. It occurs throughout Europe 

 from the Arctic to the Mediterranean, in Northern and Western 

 Asia, the Himalaya, and sparingly in North America. 



