Mosses and Lichens 



By the early writers these mosses were classed with the leafy 

 hepatics (Jungermania) on account of their manner of opening 

 the spore-case by valves instead of by a lid. They agree in 

 structure with the true mosses. Their proper place seems to lie 

 between the peat-mosses and leafy-mosses. They agree with 

 the peat-mosses because the spore-case is first enclosed in a sac- 

 like vail and then elongated on a false pedicel. They agree with 

 the genus Grimmia in habitat, manner of growth and in structure 

 of their leaves, differing chiefly in the opening of the spore-case. 



The name was given by Fredrich Ehrhart, in honour of his 

 friend J. G. R. Andreae, a Hanoverian naturalist. 



The Stone-loving Andreaea (Andrecea petrophila}, Ehrh. 

 Habit and habitat. Found in small olive or dark brown tufts 

 on wet rocks of high mountains. 



Name. From Trerpa, a rock, and fyiXelv, 

 to love, referring to its choice of habitat. 



Plants (gametopbyte) . Stems slender, $ 

 to i inch long, leafless below. 



A. petrophila. Vertica 

 section of spore-case. 



A. petrophila. Leaves. 



Leaves.-Sprea.dmg or turned to one side, lance-shaped, rough 

 on the back with projecting points; apex sometimes oblique, 

 transparent; vein none, margin incurved, entire. 



Habit of flowering. Male and female flowers on one plant 

 (monoicous) . 



Veil (calyptrd). Thin, closely fitting the spore-case. 



Spore-case. Egg-shaped, immersed in the leaves at its base 

 until maturity and then protruded by the elongation of the cel- 

 lular sheath (vaginule) surrounding its base. 



Pedicel (seta). None. 



Lid (operculum). None. 



Teeth (peristome). None. 



