TASMANIAN BRYOPHYTA. 

 Bj L. Rod way. 



(Read September 9, 1912.) 



Fam. 2— DICRANACEAE. 



Plants erect or suberect, simple or with few branches, 

 from robust down to minute forms. Leaves lanceolate to 

 subulate, with a closely sheathing base, surface smooth, 

 rarely papillose; cells oblong to linear, or m some cases 

 shorter to quadrate or rotund, longer and colourless to- 

 wards the base ; in some genera there is a patch of en- 

 larged cells, the alajrs at the basal angle. Capsule erect, or 

 more or less inclined, straight or bent, furrowed or smooth ; 

 in a few genera cleistocarpic, otherwise the lid well devel- 

 oped with a long rostrum ; peristome of 16 teeth, usually 

 cleft halfway into two slender legs ; trabeculate on the in- 

 ner, striate on the outer surface ; in some genera cleft to 

 the base into long slender papillose legs. 



The typical genera, with long smooth leaves and char- 

 acteristic capsules, a,re readily recognised. From this genera 

 recede till in Ceratodon the appearance and tissue approxi- 

 mate to the Tortulaceae. The lidless genera, Pleuridium 

 and Bruchia, are placed here by most bryologists, but they 

 do not appear to have any very pronounced affinity speci- 

 ally with this family. 



Capsule not forming a lid; plants very small. 



PLEURIDIUM: Capsule broadly oblong or sub- 

 globose. 



BRUCHIA : Capsule oblong, with a large apophysis. 



Capsule with a lid. 



Leaves papillose. 



SCLERODONTIUM : Leaves ovate, lanceolate, 

 pale. 



