— 24 — 



ditions. The usual absence of the primary thallus and the peculiar origin of 

 what may be call secondary podetia from other podetia, the dying away at 

 the base and the frequent great luxuriance are characters common to the 

 three species. The last one, like the other two, has a wide American and 

 foreign distribution, but it is more confined to cold regions than the first 

 two. 



Cladonia amaurocraea (L.) Schaer. Lich. Helv. 34. 1823. 



Primary thallus usually disappearing early, composed of small usually 

 ascending squamules, which are .5-1.7 mm. long and .i6-.2g mm. wide, 

 crenate or digitate-incised, scattered or clustered, sea-green above and 

 whitish below and covered by a continuous cortical layer. Podetia usually 

 arising from old podetia, from free fragments of old podetia or rarely from 

 the surface of the primary thallus, dying at the base and increasing in 

 length at the top, 15-120 mm. long and .5-3 mm. in diameter, cupless and 

 subcylindrical or more rarely cup-bearing, dichotomously, radiately or rarely 

 irregularly or fasciculately branched, the axils closed or rarely perforate, 

 branches spreading, the apices tapering and subulate and terminated by 

 spines, cymose branchlets or cups, forming larger or smaller clusters, erect 

 ascending or decumbent with straight apices, having a continuous or 

 areolate cortex, without squamules or sparcely squamulose toward the base, 

 straw-,colored to sea-green or rarely whitish between the areolesof the cortex, 

 usually brownish toward the apices, the basal dead portions frequently of a 

 darker color. Cups quite abruptly dilated and becoming 5 mm. in diameter, 

 perforate or imperforate, frequently oblique, the margin finally spinous or 

 radiately proliferous. Apothecia of medium size, .7-3 mm. in diameter, soli-, 

 tary or clustered at the apices of the branches, thinly margined or at length 

 immarginate, plane or convex, sometimes perforate and lobed, the disk pale 

 to brown (or even brick-red?). Hypothecium pale. Hymenium brownish 

 above and pale or yellowish below. Paraphyses simple or rarely branched 

 and scarcely thickened at the pale or brownish apex. Asci cylindrico- 

 clavate, the apical wall thickened. (Fig. 4^. 



Common in the extreme northern portion of the United States and 

 Canada, but found further south only in the mountains. Grows on earth 

 and on rocks covered by humus. Also widely distributed in foreign lands, 

 but confined to cold regions. The plant is frequently confused with forms 

 of Cladonia fiircata and yet more frequently with the next below. 

 Cladonia uncialis (L.) Web in Wigger's Prim. Fl. Hols. 90. 1780. 



Primary thallus usually disappearing early, composed of small, usually 

 ascending squamules, which are. 5-1 mm. long and .08-. 15 mm. wide, cren- 

 ate or incised-crenate, clustered or scattered, sea-green to straw-colored 

 above and whitish below, having a continuous cortical layer. Podetia 

 usually arising from old or dying branches or fragments of podetia or rarely 

 from the margin of the primary thallus, dying at the base and increasing in 

 length at the top, 25-100 mm. long and 1-3.5 mm. in diameter, cupless and 

 subcylindrical, sometimes slightly dilated in the axils, dichotomously, sym- 

 podially or radiately branched, branches all elongated or some of them short 



