138 CLASS XXn. ORDER V, 



very narrow, entire or crer.ate, of the colour of the 

 frond : frond leafy, membranous or sub-cartilagi- 

 nous, rigid, smooth and naked on both sides ; some- 

 times Cf llular or pitted ; lobed and jagged, often 

 crisped at the edges. The receptacles are rather 

 between shields and targets ; well distinguished 

 from PeUidea by its smooth, polished, membranous, 

 sub-rigid frond. 57. 2 — isianclicay (iceland lichen) 

 chesnut- greenish, ciliate-prickly. 



CoaxicuLARiA. Orbs shield-like, terminal, pel- 

 tate, thickish, cartilaginous, orbicular, flat ; at 

 length rather convex, uneven, irregular ; disk 

 generally of the colour of the frond; border scarce- 

 ly any, except in a young state a straight accessory 

 one, entire, naked, or radiated, at length reflexed : 

 frond cartilaginous, rigid, smooth, rather solid, 

 spongy within, of a shrubby tufted branched habit, 

 the branches acute. Resembles the Parmelia in 

 the frond and the Usnea in the fruit. 57. 2 — trisiisy 

 (horned lichen) brown, branches cylindric — muri' 

 cata, horns lateral and terminal. 



UsxEA. Orbs sub-coriaceous, flattened, peltate, 

 naked and smooth on both sides, mostly much di- 

 lated ; disk first concave, then flat, even, subse- 

 quently rather convex and cracked, or warty, 

 scarcely coloured ; border either none or accesso- 

 ry, which is entire or toothed in the circumference, 

 very often radiated : knobs on the same, or on a 

 different plant, which are sessile, lateral, scattered ; 

 at first shield-like and sometimes in a manner bor- 

 dered, finally convex and warty, coloured. This 

 is the filamentous lichen, tapering, more or less 

 jointed, having a central elastic medullary thread. 

 It is sometimes called tree-moss. 57.2 — Jilicaiay 

 (filamentous lichen, or tree-moss) pendant, palish 

 v/hite, orbs greenish white. 



