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 Stereocaulon is compounded of the Greek 

 <rre/?eo9, solid, and tcav\b<j, 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 S. 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, /t\a8o9, a branch, 



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