THE I1LACK MAIOKNITAIR SPLEENWORT. 



Venation of the secondary basal pinnules in the tripinnate fronds, and of the primary basal 

 pinnules in the bipinnate fronds, consisting of a Ilexuous niidvein, which, by a series of furcations, semis 

 out a vein towards each marginal tooth. If the pinnule is not deeply lolxnl, and the teeth aro simple, 

 these veins are also simple, and bear the sorus on their lower half, commencing just above their base 

 and extending half-way te the margin. If the pinnule is lobed below, one vein goes otf to each lobe, 

 and divides into venules corresponding to the number of marginal teeth, one or two of these venules 

 in the principal lobes bearing a sorus ; tho smaller lobes are occupied by one furcation of the vein; 

 these veins, however, bear on their anterior side a long linear sorus. which commences near the 

 mid vein of the pinnule, and extends beyond the point of furcation. The venules extend within the 

 scrratures, but not quite to their apex. 



Fructification throughout the back of the fromL Sort linear elongate, indusiate, on the anterior 

 side and near the base of the veins, and therefore central with respect to the pinnule ; crowded, and 

 soon becoming confluent. Indmium linear, entire, pallid, semi-transparent, and apparently violaceous 

 from the dark colour of the spore-cases showing through it. Spore-cases globose, shining brown, 

 Sfrwai ovate, angular, roughish. 



Duration. The caudcx is perennial, The fronds are persistant through the winter, so that the plant 

 is evergreen, and they aro renewed annually late in spring. 



From A, lanccolatum, which it most resembles, the Black Spleen wort may be known by its long 

 stalked triangular fronds and elongated central son, and almost always by its conspicuously stalked 

 lower pinnre ; its surface is also of a more glossy texture. 



It is a very ornamental species, and thrives moderately well under cultivation, if planted in a sandy 

 soil, well supplied with drainage material, so that water docs not stagnate about it. For outdoor 

 rockwork moderately shaded, it is exceedingly well adapted on account of its shining evergreen 

 appearance ; and if planted in porous soil among stones on a noilli aspect, it will generally flourish. 

 It does not like a smoky confined situation, and is therefore less frequently seen in a thriving state in 

 town gardens. It may be increased by division. 



The Obtuse Black Splcenwort— A. AniANTUM-xusnuM oijtusum — (Platb XXXVI., C, D) should 

 perhaps be considered rather as a less developed condition than as a variety, it being united by 

 various gradations with tho more developed plant, which we have taken as the representative of the 

 species; nevertheless, its extreme states seem to claim especial notice- It is a comparatively small 

 and dwarf plant, and assumes an ovate rather than a triangular outline. Some specimens aro not 

 more than two inches high, and others very marked in character jtro six or eight inches high. The 

 smaller specimens aro barely bipinnate, the pimue short and bluntly triangular, tho pinnules roundish 

 obovate, and very indistinctly toothed. The larger examples arc tripinnate, with their primary and 

 secondary pinnules corresponding with the pimue and pinnules of the small specimens. It is probably 

 not uncommon, specimens from the three kingdoms being before us. 



The Acute Splecnwort— A. Adiaxtum-nigruh acutum— (Plate XXXVII.) is a more distinct plant, 

 and might perhaps be separated from A. Adiantum-nigmm without much inconvenience or error. 

 There are, however, connecting links, which, in a botanical point of view, seem to indicate too close an 

 affinity to favour the separation of tho two, and suggest rather the idea that the one is the extreme 

 development of tho other The texture of the plant is tinner and less coriaceous than tho usual 

 states of A . Adiantuin-nigrmn, but some forms of the latter are uiulistinguishablc in this respect The 

 caudcx is short t'"ek, and tutted, like that of A . Adiantumrttffrum* with which it also agrees in being 

 furnished at tho crown and on the base of tho stipes with cellulosely reticulated scales, lanceolate 

 IktIow and ending in a hair-like ]H>int» as well as having elongated dark purplish brown stipes. The 

 fronds in the Irish specimens vary from about six to eighteen inches in length including the stipes, 

 and are from about two and a half to seven or eight inches across the base of the leafy portion ; in 







