THE POLYTRICHACE^E OF WESTERN NORTH AMERICA 



current or vanishing, keeled. Cells round-quadrate, distinct. Peri- 

 chaetial leaves ovate, sheathing at base, erect, narrower, subulate to 

 apex, their cells round and pellucid. 



Calyptra with a few hairs above. 



Capsule long, subcylindric, slightly arcuate, contracted under the 

 mouth, ventricose below, with numerous stomates. On wet clay 

 banks. Rocky Mountains and coast of British Columbia; 

 Washington; Oregon. 



3. Oligotrichum incurvum (Huds.) Lindb., in Hartm. Skand. Fl. 9 



ed. 2: p. 45 (1864). 

 Oligotrichum hercynicum Lam. & DC. Fl. Fr. 3 ed., 2: 492 (1805). 



Fig. 7. Oligotrichum incurvum. 



1 = Plant with capsule, dry, XL 2 = Moist plant, XL 3 = Capsule, X 5. 

 4 = Peristome, X 150. 5 = Leaf showing upper side with lamellae and in- 

 curved margin, X 15. 6 = Leaf from back showing ridges, those on vein toothed, 

 X 15. 7 = Leaf- tip showing serration of margin, X 65. 8 = Cross section of leaf 

 showing lamellae on upper side and ridges on back, X 65. 9 = Cross section of leaf 

 margin X 250. 10 = A few lamellae in cross section, X 250. 



