Mosses and Lichens 



Genus PTILIDIUM, Nees 







The species of the Genus Ptilidium grow usually in dense 

 and brownish mats, the stems prostrate or ascending, i to 2 

 pinnate or irregularly and sparingly branched, without whip-like 

 branches, the branches are lateral; root-hairs are few and short. 



The leaves are obliquely inserted, variously cut or fringed, a 

 character which suggested the name Ptilidium, derived from the 

 Greek TTTI\OV, down, the dorsal segment larger and with its tip 

 lying over the base of the leaf next above it (incubus), under- 

 leaves (ampbigastra) similar but much smaller. 



Male flowers (antberidt'a) short-stalked in the axils of more 

 closely imbricate leaves. 



Female flowers (archegonid) terminal, sometimes apparently 

 lateral because a side branch has grown on beyond the stem 

 which bears it. Bracts commonly two pairs, similar to the leaves. 



Perianth free, several times longer than the bracts, cylindrical 

 egg-shaped with constricted mouth. 



Veil (calyptra) free. 



Spore-case egg-shaped on a moderately long stalk (seta) de- 

 hiscing to the base by four rather rigid valves; spores dotted. 



Elaters two to three spiral. 



There are about eight species. 



Ptilidium ciliare, Nees. See Colour Plate XIV. 



Habit and Habitat. On fallen logs growing in loosely entan- 

 gled purple, brown,[or dark-green tufts. 



Upper view of 

 stem. 



Under view of stem to show 

 lobule. 



P. Ciliare. 



Lobule enlarged to 

 show cell-structure. 



Name. The specific name ciliare, from the Latin cilia, lash, 

 refers to the fine hairs on the margins of the leaves. 



Plants (gametopytbe).The plants have stems i to finches 

 long, mostly erect; root hairs few at the base. Branches short, 

 once or twice pinnate. 



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