NEW LICHENS. 189 
ligiata, Ach., by the narrow, semiterete thallus ; and. 
the marginal apothecia not being limited to the upper 
branches. - 
2. R. leucosticta, Tayl.; thallo pendulo, glabro, plano, fili- 
formi, dichotomo, longitudinaliter rugoso, olivaceo-rufes- 
centi, madore pellucido, ramulis incurvis ; gemmis minutis- 
^Simis, albis, numerosissimis; apotheciis marginalibus, 
minutis, planis, rufescentibus, pellucidis, margine tenui, 
integerrimo, =g 
Has. Tahiti; Beechey, Hook. herb.—Tufts 1-3 inches long ; 
the younger parts olive-coloured, the more aged reddish- 
brown. Thallus channelled beneath. In no described 
species are the soredia so minute, so crowded, or so 
white. ^ Toa ge or 
3. R. Menziesii, Tayl.; thallo compresso, lævigato, nudo, 
elongato, cinereo, laciniis filiformibus, planis, reticuloso- 
connatis; gemmis marginalibus, oblongis, pertusis, statim 
reticulatis; apotheciis substipitatis, marginalibus, demum 
.. Convexis, subimmarginatis, lutescentibus. : ii 
Has, Monterey, California ; Menzies.—Tufts pendulous. — — 
"Thallus more than one foot long, varying in breadth, — 
smooth, longitudinally striated with whitish lines. Young - 
lobes completely netted. Buds at first granulate, soon - 
elongated and stipitate, and their pertused substance € 
panding into a net-work. Apothecia occur on the more .— 
