(189 ) 
Mass.—tThe last species, presenting perhaps the ideal centre of Buellia, 
is well distinguished, not only by the spores, but by the lecanoroid 
features of its apothecia; in the next however, there is nothing externally, 
to separate the plant from ordinary states of the cluster represented by 
B. parasema.—B. oidalea, Tuck. (Lecidea, Obs. Lich. 1. ¢. 4, p. 405) in 
which the spores are perfectly muriform-multilocular, exhibiting eight to 
twelve closely approximated, transverse series, each of three to four cells, 
was found, on Oaks, in California (Mr. Wright) and occurs there also on 
Pines and Firs, and on dead wood (Mr. Bolander) as in Oregon (Prof. 
Newberry). The spores of this species are either solitary, or in twos, 
threes, fours, fives, or sixes in the thekes, and vary therefore no little in 
size; the largest observed measuring 0,046-0,088™™- in length, and 0,018- 
0,024™™- in width; but the average of more common measurements 
perhaps not ill-expressed by # micromill. Most intimately associable 
with this, and scarcely to be distinguished but as a sub-species, is 
B. penichra, an inhabitant of the living trunks, and found also on the 
dead wood of Abies Douglasii, in the Yosemite valley, California, (Mr. 
Bolander) the difference of which consists in a white thallus, and much- 
reduced apothecia, and especially in the spores (which occur, so far as 
observed, in fives and eights in the thekes) shewing no more than four 
transverse series of cells; nor exceeding 0,018-0,023™™- in length by 
0,010-0,013"™- in width. 
The few remaining, rupicoline species (Rhizocarpon, Massal.) also 
exhibit the muriform structure (fully described in Koerb. Syst. p. 258) 
and are related to the bilocular rock-Buelli@, much as B. oidalea to 
B. parasema. The most remarkable of these, as respects at least thalline 
development, is B. Bolanderi, Tuckerm.,! discovered by the unwearied 
botanist whose name it bears, in company, and often intermingled, 
with the curiously similar Biatora scotopholis (Lich. Calif. p. 24) on the 
maritime rocks of California. Thallus of minute, chestnut-coloured 
squamules, the darker colour, and always raised margins of which serve 
sufficiently to distinguish it from that of the cited Biatora. Spores 
either solitary, or in twos, or in fours, in the thekes. —— With the 
evidence before him of two North American lichens allied to the species 
1 Buellia Bolanderi (sp. nova) thallo areolato-squamuloso castaneo, areolis 
minutis cartilagineis primitus rotundatis concavis dein lobatis in ambitu elevatis 
subtus nigris; apotheciis (0™™-, 5-1™™- lat.) sessilibus plano-convexis, margine 
tenui evanido. Hypothecium fusco-nigrum. Spore in thecis saccatis 1. solitarie 
1, Que J, 4nz, ellipsoidew, muriformi-multiloculares (ser. transv. 8-12, long. 4-5) 
nigro-fusce, longit. 0,030-50™™-, crassit. 0,021-25"™-.——Sandstone rocks, Oakland 
Hills, California (H. N. Bolander) Alpine co., California, alt. 7000 ft. (Dr. Lapham). 
Almost a squamulose lichen; but the key to its thalline evolution is without 
doubt to be found in that of Lecidea fusco-atra. The reaction of the hymenial 
gelatine with iodine is blue. 
