250 43. ASPIDIUM, § POLYSTICHUM. 



point acute, tlie edge finely not spinosely serrated, the upper side bluntly 

 auricled, the lower obliquely truncate at the base ; texture very coriaceous ; 

 rachis usually scaly; veins inconspicuous; sori in two long rows. Hk.Sp.4:. 

 p. ] 0. Fil. Ex. t. 53. 



Hah. Madeira.— P. maderense, Johnst. (Ann. N. H. April, 1866), is a form with 

 piiiiite [liiinate at the base. 



7. A. (Pol^'st.) acrostic// oidex, Swz. ; st. 6-8 in. 1., densely olothed below with 

 pale-brown lanceolate scales ; fr. 1^-2 ft. L, 3-5 in. br., the pintKS of the lower 

 half barren, 2-3 in. I., j in. br., spinoso-serrated throughout, auricled at the 

 base above, the pinnse of the upper half fertile, much smaller ; texture sub- 

 coriaceous ; rachis straw-coloured, usually rather scaly ; veinlets in groups of 

 four ; sori occupying the whole under side of the fertile pinnse. — Hk. Sp. 4. p. 9. 



Hab. Canada to Florida and the Mississippi. — A. Schweinitzii, Beck, is a form with 

 lobed pinnae. 



8. A. (Polyst.) lepidocaulon, Hk. ; st. tufted, 6-9 in. 1., weak, densely clothed 

 with large cordate brown scales ; fr. 1 ft. or more 1., 4-6 in. br., sometimes 

 elongated and radicant at the point ; pimim 2-3 in. 1., -^-I in. br., lanceolate- 

 falcate, not toothed, the two sides unequal, the upper ones with a triangular 

 auricle at the base ; texture subcoriaceous ; rachis densely scaly like the stipe, 

 lower surface with scattered scales ; veins obscure, sometimes slightly con- 

 nected ; sori principally in two rows a short space from the midrib. — Hh. Sp. 4. 

 p. 12. t. 217. 



Hab. Japan and Tsus-Sima. — Habit and texture of A. falcatum, but the veins only 

 casually joined, and the rachis densely scaly. 



9. A. (Polyst.) Zowc7«2Yi5, Swz. ; st. densely tufted, 1-4 in. 1., ebeneous and 

 clothed with large lanceolate pale-brown scales at the base ; fr. 12-18 in. 1., 

 1-2 in. br., pinnate throughout ; pinnce ^-1 in. 1., j-§ in. br., ovate-rhomboidal, 

 subfalcate, the two sides unequal, the point mucronate, the edge spinuloso- 

 serrated, the upper side sharply auricled at the base, the lower obliquely 

 truncate ; rachis nearly naked ; texture coriaceous ; sori usually in two rows. — 

 Ilk. Sp. 4. p. 8. Brit. F. t. 9. 



Hab. Arctic Europe to Portugal, Naples, Greece, Himalayas, and Davuria ; Green- 

 land, and mountains of the N. United States, and British America. 



10. A. (Polyst.) mucronatum, Swz. ; st. tufted, 2-4 in. 1., stout, erect, densely 

 clothed with large reddish-brown lanceolate scales ; fr. 12-18 in. 1., H-2 in. 

 br., pinnate throughout ; piniue very numerovis, often imbricated, |-1 in. 1., 

 ^-| in. br., subrhomboidal, unequal-sided, the point mucronate, the edge sub- 

 eniire or slightly lobed, distinctly auricled at the base on the upper side ; 

 texture very coriaceous ; rachis stiff" and densely scaly ; sori in a long row on 

 each side the midy\h.—J/k. Sp. 4. p. 9. t. 216. 



Hab. West Indies. — Very like the preceding in appearance and texture. 



11. A. (Polyst.) lachenense, Ilk.; st. densely tufted, 2-4 in. ]., stout, 

 ebeneous, and clothed with large lanceolate scales below ; /;•, 4-8 in. 1., |-| in. 

 br., pinnate throughout ; pitmiv |-i^ in. 1., 2-3 lin. br., ovate-deltoid, the two 

 sides equal, the point bluntisii, the edge spinoso-serrated, bluntly lobed below 

 lialfway down ; texture coriaceous ; rachis sti'amineous, fibrillose ; sori often 

 covering the whole under side of the pinnaj. — IJk. Sp. 4. p. 8. t. 212. 



Hab. Sikkim, Hiinidayas (13-16,000 ft.) ; gathered by Drs. Hooker, Thomson, and 

 Anderson. 



12. A. (Polyst.) triangulim, Swz. ; st. tufted, 2-6 in. 1., with large dark- 



