Filices Aspidium. 549 



9. ASPIDIUM (Polystichum). 



Tufted evergreen Ferns with pinnate fronds, globose sori, and 

 a peltate orbicular indusium. Upwards of fifty species are 

 described, dispersed nearly all over the world. The name is 

 derived from a<rnis, a shield, the form of the indusium. 



1. A. aculeatum., syn. Polystichum aculeatum. This is one 

 of our commonest hedgerow Ferns, and one of the best for 

 general planting. It has large lanceolate bi- or tri-pinnate fronds, 

 of which the stipes and rachis are more or less clothed with 

 ferruginous scales. The pinnules are obliquely rhomboid, 

 auricled and mucronate or awned, and the sori are arranged in 

 a single row on each side of the midrib. There are three 

 tolerably distinct forms: A. lobatum, with bi pinnate fronds 

 and rigid sessile decurrent pinnules, confluent below ; the variety 

 lonchitidoides is still narrower, approaching Lonchltis ; A. 

 aculeatum proper has larger looser fronds with free sessile 

 pinnules furnished with spinulose teeth ; and A. angulare is 

 somewhat membranous with small stalked loose pinnules having 

 bristly teeth. This species is found in .Europe, Western Asia, 

 North America, and the south temperate regions. 



2. A. Lonchltis.- The fronds of this species are linear- 

 oblong and simply pinnate, with obliquely falcate spinulose 

 pinnules ; and the sori are arranged in two or three rows on each 

 side of the midrib. 



Aspidium falcatum, syn, Cyrtomium falcatum, is a very 

 distinct hardy Fern, from China, Japan, etc., with simply 

 pinnate rigid coriaceous shining fronds and large obliquely 

 ovate-acuminate pinnules and numerous scattered sori. A. 

 caryotideum is a variety with larger pinnules, opaque above, 

 A. Fortunei, syn. A, anamopkyllum, has narrower, more 

 numerous opaque pinnules and shorter stipes. 



10. NEPHRODIUM (Ldstrea). 



This genus differs from the last in its reniform indusium, 

 which is attached by the sinus. The sori are either dorsal or 

 terminal on the free venules in the British species. As defined 

 by Hooker and Baker, this genus comprises upwards of 200 

 species. The name is from vstypos, a kidney, the shape of the 

 indusium. 



1. N. Fllix-mas, syn. Ldstrea FUix-mas. Male Fern. A 

 very common British Fern with bi pinnate tufted fronds from 1 

 to 3 feet long, springing from a short thick rootstock, sometimes 



