

THE BLACK MAIDENHAIR SPLEENWORT. 



:*. varitffatum (W.). This exceedingly rare and beautiful variety lias l>ecn found in Yorkshire, ami 

 also in Guernsey by Mr. Jackson. It is normal in every respect, except in being striped unsymmetri- 

 cally with white ; and is sub-permanent, depending for its variegation, as Mr. Wollastou observes, on 

 the mode of culture adopted. It is quite different from the usual so-called variegations of this species. 

 Such are for the most part certainly caused by insect attacks, although one example, found by 

 Mr. Silver on Shottisbrook Church, in Berkshire, has the appearance of actual variegation, being 

 distinctly margined with yellowish- while. As it docs not appear, however, to have again been met 

 with, wc only mention it thus incidentally in this enumeration. 



4. muUifidum (W.). This differs in having tlio apex of the frond, and very rarely of the pinna, 

 bifurcate or multitid. 



5. Jlmtm (St), A curious form with a caudate frond j the pinnules being rather abnormal-looking, 

 and irregularly cut into long linear acute entire segments or lobes, answering to the acute teeth of the 

 usual states of the plant; some of the pinnules may be said to be palinatcly-laciniatc. Wo have 

 received it recently from Miss Hoscason, who gathered it near Kingsbridge, in South Devon, and, some 

 time since, from the lato Mr. Tngpen, who obtained a plant of it from a London hawker. 



fi. intermedium (M.). Under this name are included those forms in which largo size and laxity of 

 habit an coincident with an elongation of the parts, and a thin though firm texture of the fronds, such 

 forma having often been wrongly associated with acutum. From that variety they differ in their more 

 elongated and less compound fronds, and in the greater breadth of their ultimate divisions. The pinna; 

 and the fronds are caudate, but there are no linear segments of the pinnules. It seems to bear about 

 the same degree of relation to the normal slate as o&tusum, but in an opposite direction, and wo 

 enumerate it as a variety merely in order to point out the steps by which the more usual state of the 

 plant approaches the distinct-looking acute form. We have received it principally from the West of 

 England and the Channel Isles. 



7. OXyphj/Uum (M.). This form in its texture and the acuteness of its divisions lias a good deal of 

 resemblauce to the truoacufont, but it recedes from it even more than the last in the outline of the 

 frond, which though small is rather narrow and elongated, with a tendency to diminution rather than 

 enlargement of the lower pinn&X The pinna) are short* very oblique from the enlargement of the 

 basal anterior pinnule, the latter being more distinct and distant than the remainder, which become 

 a good deal confluent; the teeth are deep, narrow, and conspicuously acute. Some plants were found 

 in 1855, near Dunoon, in Argylcshire, by Sirs- East, of lilnckheatlu 



8. dicompwitum (M.). This, like aculum, is almost or even quite quadriplicate, and may be briefly 

 described as resembling that variety in tlio form of its fronds and pinnie, and oven pinnules, but the 

 ultimate parts though narrow are blunt as if rounded oft; not acute as in that, and the texture is 

 more coriaceous. The divisions, moreover, although small and comparatively narrow, are not so much 

 narrowed as in aculum, and the absence of linear segments, and the bluntness of the few teeth 

 which are apparent, readily distinguish this plant from that We have received it from the Rev. 

 J. M. Chanter, who found it at Manaton, in Devonshire. 



ft aculum (Bory). This, which has been already fully described, differs in its more subdivided fronds, 

 in which the deltoid mode of growth is usually strongly developed, in its thinner and papeiy texture, 

 and in the presence throughout of linear acute segments and teeth. As to its distinctness, the 

 preceding enumeration of varieties or forms occurring in this country shows that in composition it is 

 simulated by decomposUum, in texture by oxyphyllum especially, and by intermedium in a considerable 

 degree ; and in the presence of linear segments or teeth, both by wypfyUum, in which the teeth though 

 sharp are short, and by fi&mtn, in which latter the narrow marginal divisions are, perhaps, rather 

 abnormal developments of the teeth, than normally narrow divisions of the pinnules. These points of 

 resemblance, however, ami the occurrence of other foreign intermediate states, have determined us in 

 retaining aeutum as a variety of A. Adiantum-nii/rum* 



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