FINK—THE LICHENS OF MINNESOTA. 221 
Thallus never granulose, but more or less chinky- 
areolate, 
Thallus with plainly lobed and often black-fringed 
margin; greenish straw-colored or yellowish. .... 1. R. oreina. 
Thallus chinky or scaly-areolate, not lobed; sea- 
green to olivaceous............-...---..------- 5. R. leeanorina. 
Not confined to rocks. 
On trees or dead wood. 
Thallus and exciple thin and disappearing............ 3d. R. sophodes eri- 
gua. 
Thallus and exciple thicker and more persistent. 
Spores 20 to 35 long. ...........-.-..-2-22--+------ 2. R. ascociscana. 
Spores 14 to 22 # long. ...........22.22222222..-.- 3b. RK. sophodes  te- 
phraspis. 
Habitat various. 
Thallus coarse, verrucose and sometimes lobulate, 
whitish ..........2222.2..-2---------220-2-0-22-2+------- 3c. R. sophodes con- 
fragosa. 
Thallus finer, granulose or granulose-areolate. 
Thallus of minute granules, sometimes forming < 
subareolate crust; ashy to olive-brown.......... 3. R. sophodes. 
Thallus granulose-areolate, or scattered sub- 
squamulose; ashy to sea-green.......----------- 3a. PR. sophodes atro- 
cinerea, 
1. Rinodina oreina (Ach.) Mass. Ric. Lich. 16. /. 24. 1852. 
Lecanora straminea oreina Ach. Lich. Univ. 433. 1810. 
Thallus verrucose-areolate, except the margin which passes into distinct and more 
or less lobed squamules or somewhat elongated, branched, and usually densely crowded 
lobes, the areoles or verruce about 0.5 to | mm. across, greenish straw-colored or 
yellowish, the marginal lobes or squamules, at least, showing a thin upper pseudo- 
cortex of mostly vertical hyphze and the algal and medullary layers somewhat differ- 
entiated, suborbicular with the marginal lobes or squamules well represented, or 
becoming irregular and more widely spread over the substratum with the lobation 
tending to disappear, the more regular forms commonly 12 to 55 mm. across, the 
margin commonly more or less black-edged; apothecia small or minute, 0.2 to 0.75 
mm. in diameter, immersed or becoming adnate, or even sessile, the disk black and 
commonly flat, the thalloid exciple obtuse and entire, rarely disappearing, the apo- 
thecia then somewhat lecideoid; hypothecium pale; hymenium commonly pale 
beneath and brown or brownish above; paraphyses simple or branched, commonly 
thickened and brownish toward the apex; asci clavate; spores short-ellipsoid, 9 to 12 
long and 4.5 to 7.5 » wide. 
Generally distributed over the State. On rocks other than calcareous. 
Throughout North America, except the most southern States and southward. 
Found also in Europe. 
2. Rinodina ascociscana Tuck. Gen. Lich. 124. 1872. 
Psoroma ascociscana Tuck. Amer. Journ. Sci. 25: 424. 1858. 
Thallus a suborbicular, chinky crust, which becomes more or less concentrically 
wrinkled and passes into scaly-areolate conditions, scarcely corticate, sea-green and 
passing into a pale cinnamon-brown; apothecia small to middle-sized, 0.6 to 1.5 mm. 
or more in diameter, sessile, the disk flat or slightly convex, from pale brown to 
black, the thalloid exciple persistent, entire or crenate; hypothecium pale; hymenium 
of same color below and brownish above; paraphyses simple or rarely branched, 
commonly enlarged and brownish toward the apex; asci clavate; spores 20 to 35 yp 
long and 10 to 16 » wide. 
