156 GRIMMIACE/E. 



with few or many very short branchlets. Leaves variable in size 

 and shape, but always shorter and broader than in the last, 

 usually rather shortly acuminate from a wide ovate or almost 

 cordate slightly plicate base, spreading, flexuose, when dry as a 

 rule not much appressed, but variable ; usually, especially the 

 upper ones, ending in a hair-point of variable length, rarely more 

 than half the length of the leaf, broad, papillose, dentate, less 

 decurrent than in the last, often very short or wanting; nerve 

 thin, pellucid, faint, but usually distinguishable to the hair- 

 point ; margin revolute ; cells all strongly papillose, unistratose, 

 the upper short, sub -quadrate, sinuose, the lower long, narrow- 

 linear, nodulose, a few at basal angles wide, thin-walled and 

 pellucid, forming minute decurrent auricles. Seta long, smooth ; 

 capsule short, oval, or elliptic, slightly plicate when dry and 

 empty, brown ; calyptra and peristome resembling the last. 



Var. j3. ericoides B. & S. Usually erect, stems straight, 

 lateral branchlets very numerous, short, with a regular alternate 

 or pinnate arrangement ; leaves usually broader and shorter, with 

 a shorter hair-point. 



Hab. Barren heaths and wall tops. Common. The var. $ equally common, 

 usually by sandy roadsides or in the detritus of stream beds. Fr. spring. 



The peculiar ramification of this plant taken in conjunction with its normally long 

 hair-points, and with its habitat, usually makes its identification easy. It is, how- 

 ever, in some respects a very variable plant ; and the hair-point is especially variable 

 in length. I have very frequently found plants with the hair-point entirely wanting in 

 nearly all the leaves, one form so exactly reproducing the appearance of R. fasciculare 

 in colour, mode of growth, and leaf-form that it can hardly be separated except by 

 the papillose cells, shorter above and enlarged at the basal angles ; another with the 

 leaves very broad, flaccid, strongly plicate, very shortly narrowed to an obtuse 

 rounded apex. Under the microscope R. canescens is clearly marked off from the 

 other species by the strongly papillose cells and minute auricles. It is less eloDgated 

 and slender in all its parts than the last. 



31. OOSOINODON Spreng. 



Characters of Grimmia, especially the species of the Section 

 Schistidium, but differing in the campanulate , plicate calyptra ; 

 capsule immersed on a short seta, peristome teeth more or less 

 perforated (cribrose). Dioicous. 



Besides C. cribrosus there is another European species (C. 

 humilis) with non-plicate leaves ; a third species {C. Patersoni 

 Ferg.) has been described as Scottish, but its record as a British 

 plant was probably an error. 



