XCIV. FIL1CES. 663 



the segments broader, thinner, more wedge-shaped on the lower side, 

 much more toothed, and the lower ones sometimes almost pinnatifid, 

 the plant then forming some approach to A. spinulosum, from which it 

 differs in the much narrower frond, with the segments much broader and 

 much less divided. Sori large as in A. FUix-mas, with a conspicuous 

 indusium. Lastrea cristata, Presl. Nephrodium cristatum, Desv. 



In moist or boggy places, in temperate Europe and western Asia, from 

 the Pyrenees and northern Italy to Scandinavia, and in North America, 

 bufc not generally common. In Britain, very local, but has been found 

 in Nottinghamshire, Yorkshire, Cheshire, and Renfrewshire in Scotland. 

 Fr. summer and autumn. Some specimens appear almost to connect it 

 with A. FUix-mas, whilst others are difficult to distinguish from A. 



\spinulosum. [Lastrcea uliginosa, Newm., is a variety with more divided 

 frond and more acute pinnules.] 



7. A. spinulosum, Sw. (fig. 1293). Broad S. The most variable of 

 all our Aspidiums, allied to A. FUix-mas, but generally not so tall, of a 

 paler green, and very much broader ; the general outline nearly ovate, 

 1 to 2 feet long or rarely more, the lowest pair of pinnas not much 

 shorter, or even longer than the others. The frond is also more divided, 

 either twice pinnate, with the segments of the pinnas oblong-lanceolate 

 and deeply toothed, or pinnatifid, or thrice pinnate ; it then closely re- 

 sembles Asplenium FUix-foemina and Polypodium alpestre, but may be 

 generally distinguished by the lower pinnas not decreasing so much in 

 size, and more accurately by the sori, which are circular, with a kidney- 

 shaped indusium as in A. FUix-mas, although much smaller, and when 

 mature the indusium often disappears. 



In sheltered, shady places, on moist banks, in open, moist woods, &c., 

 common in Europe and Eussian Asia, from northern Spain and Italy to 

 the Arctic regions. Abundant in Britain. Fr. summer and autumn. 

 [More than twenty varieties of this species have received distinct names, 

 and the following four have been considered as species, but have no 

 tangible characters to separate them ; they are, 



a. A. spinulosum, Swartz. Frond oblong-lanceolate, glandular beneath, 

 pale -green. Lastrea spinulosa, Presl. 



b. A. dUatatum, Willd. Scales denser, narrower, with a dark-brown 

 centre. Frond large, broader, dark green, glandular beneath. L. 

 dilatata, Presl.' 



c. A. remotum, Braun. Eachis of frond scaly. Frond glandular be- 

 neath, oblong-lanceolate, pinnules cut halfway down. Windermere only. 

 Lastrea remota, Moore. 



d. A. cemulum, Sw. Frond triangular, glandular beneath, concave 

 and curved upwards, smelling of hay. Local in Britain. Nephrodium 

 fcenisecii, Lowe.] 



8. A. rigidum, Sw. (fig. 1294). Rigid Very near A. spinulosum, 

 of which it has the deeply toothed or pinnatifid, oblong-lanceolate seg- 

 ments, but the frond is stiffer and not so broad, and the sori are much 

 larger, the two rows often occupying nearly the whole breadth of the 

 segments, their indusiums conspicuous and persistent as in A. FUix-mas 

 and A. cristatum. Lastrea rigida, Presl. Nephrodium rigidum, Desv. 



In rocky situations, especially in limestone districts, in temperate 

 Europe, from the Pyrenees to Norway, extending eastward into central 

 Asia, and in North Amer*r, In Britain, chiefly in the limestone 



