b. L. nerved.
5. A. rupestris. Turn. (A. Rothii W. & M.) St. scarcely 1/2 inch, loosely tufted; l. imbricate, falcato-secund, longly subulate from an ovate base, thickly nerved to apex, rigid almost black; per. l. larger convolute.
Alpine and sub-alpine rocks. V. VI.
6. A. Grimsulana. Bruch. Much more robust than the last, rufous black; l. lanceolate-acute broader, more solid, falcato-secund; per. l. broadly ovate not acuminate.
Brandsley Falls, Yorkshire, J. G. Baker 1858. Herb. Kew.—Ingleborough.
7. A. crassinervia. Bruch. Tufts depressed deep black, st. prostrate ascending, fragile; l. shining falcato-secund, subulate from an oblong base; nerve thick excurrent into the round papillose subula, margin entire, cells quadrate; per. l. erecto-patent convolute nerveless.
Alpine rocks; Hebden Bridge 1865; Scotland; Snowdon 1853.
8. A. falcata. Schimp. Smaller than last, very fragile black; l. falcato-secund, opaque, from a dilated obovate base abruptly lanceolate-subulate, nerve flattened, ending at or below the apex, which is erose at margin.
Snowdon 1865 and Cader Idris (Schimper); Perthshire (McKinlay).
9. A. nivalis. Hooker. St. longer tufted slender, l. reddish brown, falcato-secund, lanceolate-subulate, acute, gradually tapering and nerved to apex.
Alpine rocks at limit of perpetual snow; Ben Nevis, &c. Summer.
