("7) 



Grimmia rivularis Brid. Lake Lindeman. On rock Dear 

 water-line. This plant has rather obtuse leaves, mostly some- 

 what sinuate dentate above. The cell walls are less thick- 

 ened and angular than in aftocarpa, and the lower cells 

 shorter rectangular and broader (593). 



Grtmmta torquata Hornsch. Sterile specimens collected at 

 Sheep Camp, Dyea Creek ; also at Lakes Lindeman and Ben- 

 nett. The typical form has leaves more or less curved and 

 twisted in various directions (596). In other specimens the 

 leaves all twist about the stem in the same direction, present- 

 ing a very rope-like appearance (598). The tufts may finally 

 become of a dull, brownish-black throughout. Some small, 

 brownish-green tufts only 1 cm. high were collected at Lake 

 Bennett, apparently young plants. The leaves are short, with 

 scarcely thickened or sinuous cell walls. Propagula, mostly 

 at the base of the costa beneath, resemble those of ordinary 

 torquata (599). 



Grtmmta ovalis (Hedw.) Lindb. {Grimmia ova/a 

 Schwaegr.) Lake Lindeman and Dawson and at various 

 intermediate points on the Yukon. Common (595). 



Grimmia tenuicaulis R. S. Williams, Bull. Torr. Bot. 

 Club, 27: 316-317. 1900. Dawson on rather dry rock walls. 

 Specimens not quite so slender as the type (590). 



Grimmia acicularis (L.) C. M. {Racomitrium aciculare 

 Brid.) Lake Lindeman (601). 



Grimmia microcarjia (Hedw.) C. M. {Racomitrium 

 Sudeticum (Hedw.) B. & S.) Lake Lindeman. Limpricht 

 states the leaf margin in this species consists of 2 layers of 

 cells, distinguishing it from heterostichum which has only one. 

 In these specimens the margin above consists sometimes of a 

 double layer, on one side, at least (602). 



Grimmia heterosticha (Hedw.) C. M. {Racomitrium 

 heterostichum Brid.) Lake Lindeman and Skagway. Leaf 

 border of a single layer of cells (603). 



Grimmia fascicular is (Schrad.) C. M. {Racomitrium 

 fascicularc (Schrad.) Bridel.) Lake Lindeman (605). 



Grimmia ramulosa Lindb. [Racomitrium microcarpum 

 (Schrad) Brid.) Lake Lindeman (606). 



