Mosses and Lichens 



Georgia 

 pellucida. 

 Spore-case 

 with veil. 



FOUR-TOOTHED MOSSES 



Genus TETRADONTIUM, Schwaegr. 



This genus was established by Schwaegrichen, but 

 differs so little from the genus Georgia that many think 

 it should not be considered a separate genus. 

 There are two species in all, one in North 

 America. 



It differs from Georgia in having both 

 teeth and stems shorter, in having the 

 spore-case oval instead of cylindrical and 

 in having the veil cover the spore-case. 

 The name is derived from the Greek 



Tctradontium TTpa, four, and 68&W, 3 tOOth. 



repandum Tetradontium TCpan- 



Sp ore-case 



with veil. dum, Schwaegr. 



Habit and habitat. Very 

 small, growing in loose clusters on 

 shaded rocks. 



Name. The specific name repan- 

 dum, the Latin for "curved," refers to the 

 margin of the mouth of the spore-case. 



Plant (gametophyte) . Stems very 

 short, bearing little gemmae at the base 

 of thread-like leafy branches. 



Leaves. Ovate-lance-shaped, rigid, 

 red-brown, closely overlapping like 

 shingles. 



Leaves at the base of the pedicel ( peri- 

 chat ial leaves). Ovate and oblong, very 

 concave, vein obscure; scales about the 

 male flowers (perigonium) smaller, 

 thinner, vein absent. 



Habit of flowering.-Male and female 



fl Qwers on t ft e same pj ant (monOlCOUS) . with male branch 



r 



Tctradontiiim 



rePMdUm ' ^ Veil (calyptra) .-Conical, resembling L?anf t^ 



branch "at* the a b i Sn P >S mitre and COVCring the SpOre- Uke^ branch on 



base. 



the left. 



case to the base. 

 Spore-case. Thick, oval, the margin of the orifice somewhat 

 notched between the teeth. 



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