508 MR. C. B. CLARKE ON THE FERNS OF NORTHERN INDIA. 
5. A. ILICIFOLIUM, Don, Prodr. Fl. Nep. 3. Frond linear or linear-lanceolate, not 
attenuated at the base, very coriaceous; both surfaces shining, naked; main rhachis 
fibrillose; pinnz subsimple, triangular or lanceolate, deeply lobed; segments ovate 
or trapezoidal, angles very spinulose mucronate; sori in two rows, usually large.— 
Hk. & Baker, Syn. Fil. 251. A. pungens, Wall. Cat. 368. 4. stimulans, Kunze; 
Mett. Farngatt. Pheg. & Asp. 43; Hook. Sp. Fil iv. 12, t. 214. Polystichum 
stimulans, Presl; Bedd. Ferns Brit. Ind. t. 31. 
Himalaya, alt. 7000—11,000 feet; from Chumba to Sikkim, frequent. 
The most marked form of this species has the pinnse simple, triangular or subrhom- 
boidal, very prickly, from being both coriaceous and spinulose; but there is a series of 
forms with longer more lobed pinnæ, till we come to a var. that is subbipinnate. There 
is one sheet at Kew with 12 fronds mounted on it, whereof 2 or 3 are A. aculeatum, 2 or 
3 are A. ilicifolium: nobody has hitherto ventured to name the intermediates. 
6. A. TuoMsoNr, Hook. Sp. Fil. iv. 7, 2nd Cent. Ferns, t. 25 partly. Frond linear, 
14-7 in., subcoriaceous, not attenuated at the base, both surfaces more or less 
fibrillose ; pinnæ lobed almost to the rhachis, bristle-serrate, very unequal at base, 
the lower margin cut away, the upper with a divaricate enlarged lobe; sori terminal 
(or nearly so) on the veins.—Hk. & Baker, Syn. Fil. 251 partly.  Polystichum 
Thomsoni, Bedd. Ferns Brit. Ind. t. 126. 
Himalaya, alt. 7000—13,000 feet; from Balti to Sikkim, frequent. 
The sheet from which Sir W. J. Hooker founded his 4. Thomsoni contains specimens 
collected on three different occasions: two of these are A. Prescottianum; one is A. 
Thomsoni. 'The plate of Hooker cited is compounded from the whole sheet, the single 
frond being 4. Prescottianum, the stipe with two fronds A. Thomsoni, as is the magnified 
pinna at the base of the plate. The descriptions of Hook. and of Hk. & Baker are drawn 
mainly from 4. Prescottianum. The two species are no doubt very close; but if a line 
can be drawn and both species retained, it must be where Beddome has drawn it; his 
figure (cited) is excellent. 
+» 
Var. gracilis. Frond small, margin of the frond crenate-lobate, hardly bristly or serrate.— 
Lastrea gracilis, (sp.) Moore; Bedd. Ferns Brit. Ind. t. 198. Nephrodium sparsum, 
var. gracilis, Hk. & Baker, Syn. Fil. (2nd ed.) 498. 
Sikkim, alt. 11,500 feet.—The type specimen is crenate ; but there are fronds on the same 
rhizome that are bristle-serrate——The genus of this fern is doubtful. The sorus is ter- 
minal or nearly so on the vein; the involucre is round, attached excentrically, the 
hinder (shorter) portion covering the vein, and having no capsules under it. When 
the involucre first separates from the frond, its summit appears excentrically concave ; 
ù. e. it is (more or less distinctly) polystichoid. But as the capsules under the front 
portion of the involucre increase in size, the front (larger) portion of the involucre is 
raised, and it appears nephrodioid; quite as distinctly so in Polystichum Thomsoni, 
Bedd., as in Lastrea gracilis, Bedd. In no form of the present species does the invo- i 
lucre appear distinetly attached lineally along the vein; on the other hand, Feet laps, no 
