180 DR LAUDER LINDSAY ON THE SPERMOGONES AND PYCNIDES’ 
y) 
“Lich. Pyrenzei;” approaches (. virescens, TUCKERM. One specimen has spermo- 
gones in little black tufts dotting over here and there the margin of the lobes. 
Alps of Dovrefjeldt, 1828; Sommerfeldt Itin. Some specimens are nigro-denticu- 
late with spermogones, as in P. nivale. The above species are all contained in 
Herb. Hooker, Kew. 
Species 4. P. citrinum, Tayl, 
A native of Java; a beautiful species, with a broad-lobed Jemon-yellow thallus. | 
The spermogones are marginal, minute brown tubercles, resembling, but scarcely 
so prominent as, those of P. nivale. 
Species 5. P. glaucum, Hoffm., 
Which occurs in Europe, America, and Asia. KorBer says, “ Spermogonien sah 
ich noch nicht,” and certainly they are not very common. 
Specimen 1.—Sierra de Estrella, Portugal; WeEtwirzscu, “ Crypt. Lusitan.” 
No. 116. The thallus approaches var. fallax, Sch., in the division of its lobes 
into lacinize, which again have their margins frequently studded over with isi- 
dioid growths. The spermogones are marginal, crowded, indistinct, minute, 
brown tubercles, which add to, though they seldom of themselves give, a denti- 
culate character to the margins of the lobes. 
Specimen 2.—Var. fallax of authors ; Scotland; in the Menziesian Herbarium, 
Royal Botanic Garden, Edinburgh. The plant bears no apothecia; the lobes are 
laciniate, and their margins isidiiferous. Some of the specimens belong, undoubt- 
edly, to Parmelia perlata, with which this Platysma is frequently confounded, 
especially the var. fallax of the latter with var. ciliata of the former. The sper- 
mogones of the Parmelia are, however, quite different from those of the Platysma. 
They are punctiform, black, immersed, and scattered on the flat surface of the 
lobes of the thallus near their margin. In this Scotch specimen of var. fallaw — 
there are no spermogones ; but a few occur in a specimen of the same var. from 
the west coast of North America, 1787; collected by ALEx. Mrnzres himself. 
Apothecia occur at the ends of the lacinie; the margins of which laciniz and 
lobes are very isidioid. The tooth-like isidia are sometimes tipped with spermo- 
gones; but the majority of them are sterile. American specimens of some other 
Platysme are occasionally spermogoniferous, while British specimens are not,— 
such is P. sepincolum. 
Species 6, P. lacunosum, Ach., 
Its spermogones are marginal, as in the preceding species, between which and P. 
ciliare it is intermediate in regard to their size and appearance. 
Specimen 1.—West coast of North America; Oregon, ScouLeR; in Herb. 

