Mosses and Lichens 



Genus STEREOCAULON, Schreb. 



The vegetative organ or thallus is two-fold, consisting 01 a 

 scale-like (squamulose) or granulose, horizontal growth which 

 usually disappears, and a vertical growth which becomes shrub- 

 like, with fruit-bearing branches (podetia). The podetia are 

 solid and clothed more or less with a white powder (soredia) 

 and with granules (phyllocladia) which become scale-like or pass 

 into coral-like branchlets. 



The fruiting organs (apothecia) are at first little disks soon 

 becoming convex; solid, terminal, or lateral; dark-brown, or 

 black. 



The generic name Stereocanlon is compounded of the Greek 

 o"re/)09, solid, and /cauXo?, a stalk. 



When dry these lichens are very brittle, but when moist they 

 may be handled freely. 



Stereocaulon paschale, (L.) See Plate VIII. 



Habitat. On rocks. 



Vegetative organs (thallus}. Primary, usually wanting. 

 Secondary, growing in round thick mats; podetia long and 

 slender, much branched and covered with scale-like (squamulose'), 

 crenate, dark-gray granules and inconspicuous cottony fibres. 



Fruiting organs (apothecia). At or near the apicus of the 

 podetia, small, with disk convex dark-brown. 



Name. The specific name paschale is the Latin for "Pass- 

 over." Its significance is not evident. 



NOTE : 5. paschale is closely related to 5. tomentosum which is as its 

 name implies conspicuously covered with cottony fibres. 



Genus CLADONIA, Hoffm. 



The horizontal thallus of the Genus Cladonia is scale-like, 

 rarely granulose; and may or may not persist. 



The fruiting branches (podetia) are hollow, sometimes opening 

 to the exterior; leathery, cup-shaped, or funnel-shaped; some- 

 times shrub-like, and very much branched; rarely club-shaped. 



The fruiting organs (apothecia) are usually little heads (cepha- 

 loid) hollow within, they are variously coloured, but never black. 

 The spores are ovoid-oblong; simple; colourless. 



The generic name Cladonia from the Greek, /cXaSo?, a branch, 



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