OF FILAMENTOUS, FRUTICULOSE, AND FOLIACEOUS LICHENS. 297 
irregular, stellate-fissured perforations, which are the ostioles of old spermogones. 
The spermatia are rod-shaped or acicular, about z th to auth long, and saath 
broad. The sterigmata are about mth to ath long, and consist of three to six 
_ delicate, cylindrical articulations, which are sometimes very irregular in form; 
their breadth is frequently jsanth to gath. As in P. physodes in all its forms and 
varieties, along with the spermatiferous sterigmata occur numerous elongated, 
ramose, delicate filaments, that project into and fill up the cavity of the spermo- 
gone, which issimple. Occasionally the spermatiferous sterigmata would appear 
to become elongated and hypertrophied, and to anastomose. In one specimen from 
Connemara, pycnides occur interspersed among the spermogones, of which they 
have all the external aspect, and from which, outwardly, they cannot be distin- 
guished. The stylospores are very irregular in form,—spherical, oval, or pyriform 
chiefly,—sometimes curved, about auth long, and gath broad, on short, simple, 
linear sterigmata. Pycnides, associated with the ordinary spermogones of the 
plant, and having almost the same characters as those now described, occur in a 
specimen of P. sinwosa, from Dunkerron (vde page 216). It is curious that both 
the Parmelias in which these pycnides occur are Jrish specimens! KorpBer 
appears to me to err greatly where he describes the spermatia of P. sazxatilis as 
- almost spherical “‘ kugligen spermatien.” Ihave never seen them otherwise than 
straight and linear, of great tenuity throughout. 
Specimen 1.—Form furfuracea. It is almost uniformly on this state or form 
of P. saxatilis that spermogones occur; but generally only where the ends of the 
lacinize are smooth and free of furfuraceous or isidioid growths. Blaeberry Hill, 
Perth, April 1856, W. L. L. Most of the lacinize are broad or lobate, with rounded 
margins ; these laciniz are found especially at the periphery of the plant. More 
centrally the lacinie are narrower, with retuse or truncate ends. It is on the 
latter, and not the former, that spermogones occur. 
Specimen 2—Birnam Hill, Dunkeld, 1856; with apothecia; W. L. L. Some 
of the lacinize are studded over with black stellate-fissured perforations, which 
are the ostioles of old spermogones. Craig-y-Barns, Dunkeld, April 1856, 
W.L.L.; with apothecia. The general surface of the plant is furfuraceous; but some 
of the lacinize have smooth, glaucous ends, on which occur a few large, degenerate, 
maculiform spermogones. Craig Vinean, Dunkeld, May 1856, W. L. L. Some of 
the lacinize are very narrow, and all are of a bluish-gray colour, and smooth to- 
wards the ends. Old wall, Amulree Road, Dunkeld, June 1856, W. L. L.; with 
apothecia. The lacinize are narrow, and the punctiform black spermogones are 
sparingly scattered in groups at their extremities. 
Specimen 3.—Hills above Abernethy and Newburgh, May 1856, W. L. L.; with 
apothecia. Here the spermogones, which have mostly depressed ostioles, are 
scattered among the isidioid growths which cover the thallus. 
Specimen 4.—On roadside walls, Linn of Dee Road, Braemar, August 1856, 
