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dium elongatum Sw., as formerly supposed, (See Hook. Bot. Misc. New Series, I. pp 25, 26.), may very possibly be Aspidium spinulosum of Herr Höll's List.

5. Nephrodium affine, nob. in Bot. Misc., New Series, I. 25.

N. fronde subtus hirsutiusculo, bipinnatifido; pinnis inferioribus brevioribus: pinnulis approximatis oblongis, subintegris; apice truncatorotundatis, minutissime eroso-denticulatis; basi tota adnatis: incisuris deorsum acuminatis, sursum latioribus: pinnulis superioribus confluentibus: soris biseriatis distinctis: stipite rhachibusque densissime paleaceis. Hab. rarior in Madera umbrosis, ab alt. 1500 ad 3500 pedum.

Fronds two or three feet long, disposed in a coronet or circle; beneath with scattered hairs, of a chaffy nature, at the margins and on the nerves of the pinnules. Stipes and rhachis throughout most densely chaffy; the chaffs or scales remarkably large as well as copious. Lower two to six pair of pinnæ smaller and shorter than the middle ones; the lowest very much so. Pinnules closer together than in N. Filix mas: all of them, even the uppermost rounded (not merely obtuse) at the apex; the lowest even truncate. In N. Filix mas the uppermost are acute, and the lower sometimes scarcely obtuse. The sides of all in N. affine are nearly entire, or with distant, scarcely perceptible, shallow teeth upwards; not in the least incised, or with any tendency to a higher degree of decomposition, like those of N. Filix mas, or of N. elongatum; their rounded apex irregularly notched with very minute shallow teeth, quite different from the obvious serrated teeth of N. Filix mas, and without a lens, scarcely perceptible; the pinnules appearing entire. Incisures (i. e. the spaces between the pinnules) acute at the bottom, i. e. towards the nerve, and widening upwards or rather outwards; evidently not reaching to the nerve or midrib, as they appear to do in N. Filix mas, though really they do not. Hence the base of all the pinnules is in no degree incised on either side, as in N. elongatum; but the pinnules are adnate by the entire breadth of their base: neither is their lower side arcuato-decurrent as in N. Filix mas; but the base is truncate and the opposite sides or margins of each pinnule are parallel to each other down to its very bottom, where they

are both at right angles to the rhachis: whilst in N. Filix mas, the lower or inner margin, i. e. that towards the main rhachis, quits its condition of parallelism with its opposite upper or outer one towards the base, and forms a curve downwards towards the pinnule next below it; which is what I have called arcuato-decurrent. Thus the incisure in N. Filix mas is either irregular, or abrupt, open, and broad at the base; not regularly acuminate; so that the spaces between the pinnules being larger, or at least not regularly narrower downwards, these last appear more remote and distinct than in N. affine. In fact the incisures (not at all the pinnules) of N. affine rather resemble those of Nephrodium (Aspidium Auct.) Oreopteris than of N. Filix mas. The pinnules of the lower pinnæ, instead of having any tendency by incision to a farther degree of decomposition, as they have both in N. Filix mas and N. elongatum, are quite simple, and even more entire than the upper ones. Sori precisely similar in their arrangement and indusia to those of N. Filix mas.

I possess specimens of N. affine from various localities, differing in exposure, shadiness, and elevation; but all agree in the foregoing characters. By these, this fern approaches nearer to N. elongatum than to any other Maderan species: the true European N. Filix mas being the connecting link; from which it is curious to observe, these two Maderan ferns reciprocally recede in opposite directions: N. elongatum having the serratures much more aristate, and the stipes and rhachis, especially the latter, less chaffy than the European N. Filix mas; while N. affine has the serratures much less developed, but the stipes and rhachis much more copiously chaffy than the same.

The specimens of N. Filix mas, which I have particularly examined for comparison with N. affine, are British only: but my friend Mr J. Bennett has also compared specimens in the Banksian Herbarium, and noticed the same differences. Indeed his observations, exactly corresponding with my own, here made before and apart, have led me with considerable confidence to the conclusions and results here stated.

I subjoin, for facility of comparison, the specific characters of N. Filix mas and elongatum; eliminated however solely in reference to the three present species,

Nephrodium Filix mas.

N. fronde glabro, bipinnato: pinnis inferioribus brevioribus: pinnulis subremotis, oblongis, obtusis, serratis, adnatis, basi inferiore arcuato-decurrentibus; inferioribus serrato-incisis; superioribus confluentibus: soris biseriatis distinctis: stipite paleaceo; rhachibus sparsim paleaceo-hirtis.

Aspidium filix mas, Auct; Linn. Sm. Hook. &c. From English specimens, gathered at Dale Abbey in Derbyshire.

Main rhachis sparingly hairy rather than chaffy, and the nerves and margins of the pinnules beneath are not at all hairy. Pinnules subremote; so that the incisures are truncate or oblique at the base, or as wide at the bottom as at the top in the lower pinnules.

6. Nephrodium elongatum.

N. fronde rigido, glaberrimo, bipinnato: pinnulis oblongis, spinulososerratis; superioribus apice rotundatis, confluentibus; inferioribus sublanceolatis, acutiusculis, crenato-incisis, distinctis, subpetiolatis s. basi utrinque incisis; incisuris triangulari-decurrentibus: soris biseriatis, confertis, subimbricatis nervo approximatis; indusiis glanduloso-scabris: stipite elongato rhachibusque pallidis, paleaceis; paleis rhachidum raris, sparsis, distinctis, squamiformibus.

N. elongatum, Hook. et Grev. Icon. Fil. t. 234.

Aspidium elongatum, Sw., &c.

Hab. in Madera ab alt. 1500 ad 5000 ped. vulgaris.

Fronds not growing in a circle, of a much lighter and brighter green than in the two preceding species, and of a rigid brittle texture: with a greater tendency to a farther degree of decomposition than even N. Filix mas. Pinnæ, in full-sized specimens of 3 or 4 feet long, more remote and distinct; the lower ones not shorter than the rest, but rather the contrary. Upper pinnules close together; so that their edges often touch or even overlap each other, concealing the incisure; except at the base, where, by the incisure being produced downwards into the substance of the pinnule next below, and similarly, though in a less degree and sometimes not at all, into the pinnule next above, there is formed in all a kind of triangular hole, or open space, quite

different from any thing in the two preceding species; though of the two, most like N. Filix mas. Hence the incisures, not the pinnules, are decurrent: the lower base of the pinnules, as well as the upper in a less degree, being notched by the incisure, and their margins being parallel at the base.

7.

Cheilanthes maderensis, nob. in Bot. Misc. New Series, I. 26.

C. fronde oblongo-lanceolato vel ovato, bipinnato, glabro: pinnulis (s. laciniis secundi ordinis) oblongis, obtusissimis, adnatis, decurrentibus, sinuatis; inferioribus basi pinnatilobatis; superioribus confluentibus; omnibus vel omnino vel superne indivisis, foliiformibus, crenatis ; lobis fructiferis rotundatis: indusiis interruptis, incisis; lobis rotundatis vel truncatis, margine integro: stipite rhachibusque paleaceo-hirtis.

Hab. in fissuris rupium prope urbem Funchalensem Maderæ; etiam in muris ipsius urbis.

Species cum aliis quibusdam diu confusa, revera distincta videtur. A Ch. suaveolente Sw. (Polypod. fragrans Desf. Fl. Atl. ii. 248. t. 257) prima facie differt fronde multo minus tenuiter diviso, nec leptophyllo; divisionibus sc. magis foliaceis, confluentibus nec distinctis; pinnulis oblongis, sinuatis crenatisve, multo majoribus, foliiformibus, omnino vel superne saltem indivisis; summis confluentibus; omnibus basi tota adnatis decurrentibusque, nec puncto tantum centrali baseos s. petiolulo rhachi affixis: soris indusiisque incisis, interruptis, nec continuis ut in figura 1. iconis jam citatæ delineantur. A Ch. odora Sw., planta sc. Helvetica et Pedemontana (Adiantum pusillum All.), iisdem characteribus, necnon fronde bipinnato nec tripinnato, indusiisque margine integris, nec laceris, subciliatis" Sw., satis superque distincta videtur: huic vero speciei procul dubio, monente amico J. I. Bennett, affinitate proxima. Ch. fragrante Sw., stirpe Indiæ Orientalis, cui cl. Swartzius olim dubio animo conjunxit, "forsan speciem diversam" tamen monens, magis ac magis recedit: quum ne alia dicam, illa pinnulis "oppositis, ovatis, subpetiolatis, lacinulis 2-3-partitis," tenuibus; earum "segmentis subacutis, apice soriferis" (monosoris); "soris minutissimis;" indusiisque dentiformibus distinctissima est. In stirpe Maderensi pinnulæ haud raro alternæ ; in tribus supra indicatis potius oppositæ videntur.

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[blocks in formation]

P. panicula lanceolata, stricta, contracta, densa, subsecunda; spiculis 4--6-floris, glumis multo longioribus: culmis basi decumbentibus, ramosis; foliis planis mox convolutis, strictis, cuspidatis, glaucis.

Hab. in Maderæ ora maritima rariss.

Obs. P. communi Trin. (Arundini Phragmitæ L.) proxima, et forsan varietas tantum. Culmi basi ramosi, frutescentes, nudi, tenacissimi, late procumbentes; apice foliosi, ascendentes 2-4-pedales: foliorum margine subserrulato; vaginis apice, nodisque plerumque barbatis. Gluma inferior brevis, acuta, superior inferiore duplo longior, remota, acuminata. Paleæ inferiores florum inferiorum productæ, flores superiores longitudine subæquantes; omnes lanceolatæ, acuminatæ, glabræ. Rhachis supra florem inferiorem longissime sericeo-pilosa. Palea superior brevis, oblonga, plana, binervis, subciliata. Panicula erecta, arctissime glomerata, congesta, densissima, multiflora, 3-6-pollicaris longa, 1-2-lata, pallida, flavescens; demum albo-sericea. Radices repentes.

9. Deschampsia argentea, nob. (Aira argentea nob. olim Prim. in Trans. Cam. Phil. Soc. IV. I. p. 9. No. 8.) Species distinctissima, D. cespitosa Beauv. (Airæ cespitosa L.) proxima. Deschampsia Beauv. species legitima. Pedicelli, floresque basi dense pilosi. Palea inferior apice 3-4-dentata. 10. Avena marginata, nob.

A. glaberrima, lævis: panicula simpliciuscula, coarctata, subsecunda; spiculis 4-5-floris, glumis sublongioribus; rhachi pedicelloque floris alterius superioris abortientis villosis; floribus omnino glabris s. nudis, scabriusculis; palea inferiore apice quadriseta; s. bifida, laciniis bifidis in setulas productis; dorsi medio arista geniculata: foliis distichis, brevissimis, obtusis, carinatis, marginatis, rigidis, glaucis; ligula lanceolata, producta: radice fibrosa, subcespitosa, perenni. O'

In rupibus Maderæ excelsis nuperrime invenit am. Car. Lemann, M. D. usbry

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