FINK—THE LICHENS OF MINNESOTA. 93 
Not parasitic on other lichens. 
On rocks. 
Thallus sea-green or ashy, flat-areolate; spores 9 to 
16 » long and 4 to 7.5” wide................------ 1. B. spuria. 
Thallus gray to brownish or reddish brown; spores 25 
to 38 » long and 11 to 17 » wide.............-.---- 12. B. badioatra. 
On trees or old wood. 
Thallus usually sea-green or ashy. 
Thallus commonly smooth, rarely areolate, 
thicker. 
Spores normal; apothecia small to middle- 
sized.....--2-----2--2020 20222000 2. B. parasema. 
Spores 3 or 4-celled; apothecia as above .... 2a. B. parasema_ tri- 
Thallus thin, scurfy or chinky, phragmia. 
Spores 8 in each ascus; apothecia minute 
and black. .........2.....-.-.-..---------- 4. B. myriocarpa. 
Spores 12 or more in each ascus; apothecia as 
ADOVE..... 2. eee eee eee eee eee eee eee eee 4a. B.myriocarpa 
polyspora, 
Thallus not sea-green. 
Thallus whitish-ashy; spores 19 to 31 ” long and 
7 to ll yw wide...........-..22.2.------------ 3. B. dialyta. 
Thallus brownish-ashy. 
Thallus verrucose and becoming areolate 
(rarely on rocks); spores 9 to 15 » long and 
4to7 » wide.............--.------------ 5. B. turgescens. 
Thallus scurfy, granulate, or sorediate; 
spores 6 to 10 « long and 2 to 4 » wide.... 6. B. schaereri. 
1. Buellia spuria (Schaer.) Arn. Flora 55: 291. 1872. 
Lecidea spuria Schaer. Lich. Helv. Spice. 3: 127. 1827. 
Thallus more or less roughened and areolate, the areoles small and flat or becoming 
more or less convex and commonly multiangular and black-edged, either scattered 
upon the conspicuous so-called hypothallus or crowded into a continuous crust, sea- 
green or more commonly ashy-gray; apothecia small, 0.4 to 0.8 mm. across, adnate or 
immersed, the disk black and flat or slightly convex, the exciple black and prominent 
or rarely disappearing; hypothecium dark brown; hymenium pale or slightly brown- 
ish, especially above; paraphyses simple or rarely branched, commonly enlarged and 
brownish toward the apex; asci clavate or inflated-clavate; spores brown, ellipsoid or 
oblong-ellipsoid, frequently somewhat constricted at the septum, 9 to 16 » long and 
4 to 7.5 » wide. 
Collected in several places in the southwestern portion of the State. On rocks 
other than calcareous. 
The plant has a wide North American distribution and is also known in Europe and 
Africa. 
a 
2. Buellia parasema (Ach.) Koerb. Syst. Lich. 228. 1855. 
Lichen parasemus Ach. Lich. Suec. 64. 1798. 
Thallus commonly continuous and smooth, but often becoming thicker and rough- 
ened, chinky and finally areolate, but even showing occasionally granulate conditions, 
sea-green, ashy, or darkening, or even yellowish, bordered more or less by a black 
margin, the so-called hypothallus, rarely scattered upon the substratum as in the last; 
apothecia varying considerably in size, sessile or rarely adnate or even more or less 
immersed in specimens having thicker thalli, the disk usually flat and surrounded by 
a thin black exciple or becoming convex when the exciple (as rarely) disappears, the 
