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THE CRESTED BUCKLER FERN. 



OKOOBAPUICAL DISTR1 1IUTIOX.— Thi» Koni i» A gciirrttll/ iLiiptred European vpcoic^ ttramog from \h* Srsadiiw- 

 vinn VinptL-im* to July aihI IltimruY. tt n!*o <wvum in Xortli Anirrtai, both in tbo Unitfd State* ocd C*ftJUb T ia 

 two or llirf* form*, on* of which u ibc AtpiJittm I<t*t*tttt*n*r t and another 11 \wy griwrallj imtuketi for ibo 

 X Orflfatmum. Tl Itai *Iao boon nbfciinri! from the SUtc It*w in Norte W«t Auwrta <//*. //-■--<-... IV nrirtj 

 u/tj'iAOfti Oixum in GtrmAnj &t not) ah in Pn^UnJ, 



Candez stoutish, decumbent, or slowly creeping, t. e< extending in a horizontal direction, the 

 fronds of each season being in advance of those of the preceding one; branched, scarcely tufted, 

 somewhat scaly, formed of tho enlarged living bases of the decayed fronds surrounding a woody 

 axis. Scales similar to those of the stipes. Fil/m* numerous, coarse, dark brown, branched. 



jSfrjwtf tenniiial and adherent to the caudox, about one-third of the entire length of the frond, stout, 

 shining, dark brown at the base, the brown blending with green upwards, sparsely scaly, with broad 

 ovate membranous pale-brown scales, which are for the most part apprcssed, and arc most numerous 

 near the base. Rachis stout channelled in front, almost free from scales, pale green. 



Vernation circulate, the pinme lying Hat against the sides of the incurved rachis. 



Frond from one to three feet high, herbaceous, dull green, erect, narrow linear-oblong, tapering 

 at the apex, scarcely at all narrowed at tho base, sub-bipinnatc. Pimm numerous, the lower ones 

 distant, sub-opposite, broad triangular, two inches long, an inch and a half broad at tho base; tho 

 upper more contiguous, alternate, elongate triangular, those near the middle of the frond measuring 

 about two and a half inches long, and nearly an inch and a quarter broad at the base; all shortly 

 stalked, the stalk twisted so that their upper surface is directed towards the apex of the frond. Pinnules 

 Oblong, blunlislt, all more or less adnate,and connected by the wing of tho rachis ; the basal ones only, 

 and these only on highly developed fronds, having a narrow attachment, pinnatiiidly lobed, the lobes 

 serrate, with sphuilosc teeth ; the rest of the pinnules are inciso-crenato at the margin, serrate 

 at the apex, the crenatures serrated, ami all the scrratures tipped by a spinulose point ; the posterior 

 basal pinnules are scarcely larger than tho anterior ones of the same puime. The late summer and 

 autumnal fronds have broader and larger pinnules. 



Venation of the pinnules consisting of a flexuous midvein, which throws off a rein into each lobe ; 

 these veins bear several venules, which are either simple or forked, and are directed one towards 

 each tooth, terminating within tho margin in a somewhat thickened point Usually only the anterior 

 basal vemde of each fascicle bears a sorus, but occasionally on the lowest pinnules the posterior basal 

 venule also is fertile. The veins are conspicuously depressed on the upper surface. 



fructification on the back of the fronds, usually confined to the upper half, but sometimes 

 extending lower down. Sort numerous, round, indusiate, medial on the anterior basal venules, 

 in a row on each side of and nearer to the midrib than the margin, except in the most luxuriant 

 pinnules, where the development of sori on the posterior venules produces a more irregular arrange- 

 ment fndustutti membranaceous, reniform, flat, with a wavy, somewhat irregular margin, but 

 without glands, affixed by a deep basal sinus. Spore-cases numerous, dark brown, roundish. 

 Spores oblong, muriculate. 



Duration. The caudex is perennial. The fronds are annual, tho earliest produced in May, succeeded 

 by others during tho summer, all destroyed by the autumnal frosts, or eventually perishing if not 

 exposed. 



lastrea crisUtta, with the plants called utigimsa and spintdom, form a group, distinguishable 

 by habit and other characters from the allied dilatata group, with which, however, the more highly 

 develojKrd form, spinufosa, is sometimes associated by botanists of high authority ; in consequence, no 

 doubt, of the plants having been studied in the herbarium, where their differences become less marked, 

 rather than in a state of growth, in which the most important characters are obvious. Of this group 

 L. crisUUa is the least developed form. We have in the Handbook of British Ferns (see p. 114) 



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