180 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
A variable lichen. A rather large-fruited form, collected on limestone at St. Cloud 
by Mr. Arthur Morgan, has been referred by Dr. A. Zahlbruckner to Lecanora dispersa. 
This plant, however, seems quite as much at home with the present species and in 
some respects appears quite like certain forms of Lecanora subfusca. 
The species is generally distributed over the State. On rocks and old wood. 
Distributed throughout North America. Known also in Europe and Asia. 
EXPLANATION OF PLATE 34.—A, Plant of Lecanora hageni on rocks, showing the apothecia. B, Plant 
of Pertusaria velata on branch of tree, showing the crustose thallus and the apothecia. A enlarged 1g 
diameters; B, 1} diameters. 
9. Lecanora dispersa (Pers.) Floerke, Deutsch. Lich. 3: 4, 1815. 
Lichen dispersus Pers. Ann. Bot. Usteri 7: 27, 1794. 
Thallus of scattered and small and inconspicuous dirty greenish or whitish scales 
or granules, or entirely disappearing, or in a form on limestone, continuous beneath 
the clustered apothecia, these covering areas from 5 to 20 mm. in diameter; apothecia 
also scattered or more rarely clustered, commonly minute, but sometimes larger, 
0.4 to 1.5 mm. in diameter, adnate, when crowded more or less angular, the disk flat, 
yellowish-brown to olivaceous, the exciple much as in the last, sometimes more or 
less pruinose and more inclined to entire conditions; hypothecium pale; hymenium 
pale below and commonly somewhat darkened above; paraphyses simple or rarely 
branched, quite inclined to cohere, sometimes sligthly enlarged and darker toward 
the apex; asci clavate; spores ellipsoid, 8 to 12 » long and 3.5 to 5.5 » wide, thus 
somewhat smaller than in the European plants examined. ’ 
Closely related to the last above, but generally regarded as a distinct species. 
Collected at Warroad, at Le Clair, and at Rainy Lake City. On old wood. <A plant 
from the limestone at St. Cloud has been referred here by Doctor Zahlbruckner. See 
note under Lecanora hageni. 
Elsewhere in North America in Labrador or Newfoundland. Known also in Europe, 
Asia, Africa, and New Zealand. 
10. Lecanora sambuci (Pers.) Nyl. Not. Sallsk. Faun. Flor. Fenn. 5: 168. 1861. 
Lichen sambuci Pers. Ann. Bot. Usteri 7: 26. 1794. 
Thallus crustose and rather thin, smooth or passing into granulose or subleprose 
conditions, spread over the substratum in rather large and usually irregular patches, 
35 to 90 mm. across, whitish or ashy in color, in ours the crust continuous and usually 
consipcuous by its color, but said sometimes to disappear almost entirely; apothecia 
small or minute, 0.5 to 1 mm. in diameter, adnate, the disk flat or convex, flesh-colored 
to light brown, the exciple white or whitish, in ours entire or subentire and rarely 
disappearing, said to be crenulate in European specimens; hypothecium pale; 
hymenium pale throughout or somewhat brownish above; paraphyses simple or 
rarely branched, sometimes slightly enlarged and darker toward the apex; asci clavate 
or ventricose-clavate; spores ellipsoid, 8 to 12 » long and 5 to 7 » wide, varying from 
8 to 32 in each ascus, in ours usually 12 to 16. 
Collected in the northeastern portion of the State at Grand Portage, in the Misquah 
Hills, and at Tofte. On trees, especially balsams. 
Elsewhere in North America in Massachusetts and Illinois. Known also in Europe. 
11. Lecanora varia (Hoffm.) Ach. Lich, Univ. 377. 1810. 
Patellaria varia Hoffm. Descr. Pl. Crypt. 1: 102. pl. 23. f. 4. 1790. 
Thallus crustose and thin, thick, or even disappearing, smoothish or verrucose- 
urceolate, suborbicular, 15 to 60 mm. in diameter, or irregular and widely spread over 
the substratum, pale greenish, yellowish, or whitish; apothecia small or minute, 
0.4 to 1 mm. in diameter, adnate or more or less immersed, the disk flat or convex 
and flesh-colored or passing into yellowish or buff, the exciple entire or crenulate, 
sometimes disappearing; hypothecium pale; hymenium of the same color below and 
