FIGS. 



PLATE XXXIX. 



[Proc. Wash. Acad. Sci., Vol. IV, PI. XXII.] 

 a-f. Polytrichum yukonense. 



a. Entire plant, natural size. 



b. b. Leaves ( X 13)- 



c. Transverse section of a leaf ( X34) 



d. Transverse section of a lamella ( X I 35) 



e. Part of a lamella seen from side ( X 270). 

 :,y. Basal areolation of the leaf ( X I 35) < 



2, a. Polytrichum jensenii. 



2, a. Basal areolation of the leaf ( X J 35)' 



3, a e. Brachythecium beringianum. 

 3, a. Entire plant, natural size. 



3, . Stem leaf ( X 26). 



3, c, c. Branch-leaves ( X 26). 



3, d. Basal areolation ( X I 35) 



3, e. Cells in the middle ( X 270). 



4, a e. Plagiothecium fallax. 



4, a. Entire plant, natural size. 



4,3. Leaf (X 13). 



4, c. Perigonial leaf ( X 26). 



4, d. Basal areolation of a leaf ( X T 35) 



4, e. Areolation in the middle ( X I 35) 



5, a-e. Hypnum treleasei. 



5, a. Entire plant, natural size. 

 5, 3, 3, b. Leaves ( X 2 6). 



5, d. Basal areolation of a leaf ( X 270). 



5, e. Cells in the middle ( X 270). 

 [366] (326) 



