THE SPLEENWORTS. 



57 



manner within this small space, so that when from age the 

 sori burst open the indusium, the spore-cases form a con- 

 fluent mass over the whole under-surface. 



The confluent mass of spore-cases arising from the crowded 

 position of the sori, has led some authors to consider this 

 plant an Acrostichum, the mark of which is to have the whole 

 under-surface thus covered. Some of the sori being face to 

 face, growing as they dp from the inward side of each vein, 

 and almost in juxtaposition, has again led other botanists to 

 think it a Scolopendrium, the mark of which is to have the 

 sori confluent in pairs face to face. If, however, the plant is 

 gxamined while young, it will be seen that these resemblances 

 are unreal, and that it is truly an Asplenium. 



This rare Fern is found in the West of England, but more 

 abundant in the North and in Ireland. It is found on rocks 

 and walls. 



In cultivation it requires sandy peat-soil FlG - 14 - 

 mixed with rubbly porous matter ; and in 

 uncongenial situations the shelter of a 

 close-frame, or bell-glass. 



ALTERNATE SPLEENWORT. 



This is Asplenium germanicum, its syno- 

 nyms being Asplenium alternifolium, Asple- 

 nium Breynii, Scolopendrium alternifolium, 

 and Amesium germanicum. 



It is one of the rarest of our native Ferns, 

 and perfectly distinct from A. Ruta-mura- 

 ria, of which some botanists have thought 

 it to be a variety. It grows in little tufts, 

 the fronds being from three to six inches 

 high, sub-evergreen, narrow-linear in form, 

 pinnate, divided into distant, alternate, 

 wedge-shaped pinnae, one or two of the 

 lowest having generally a pair of very deeply 

 divided lobes, the upper ones more and 

 more slightly lobed, all having their upper 

 ends toothed or notched. The fronds are 

 quite small, and the parts narrow, which, 

 added to their opacity, renders the venation 

 indistinct ; there is no midvein, but each 

 pinna or lobe has a vein entering from the 

 base, which becomes two or three times 

 branched as it reaches the broader parts 

 upwards, six or eiglit veins generally lying 



