Mosses and Lichens 



Leaves. Leaf-cells spreading or appressed, flat or concave; 

 variable in size and shape, lance-shaped to ovate-lance-shaped or 

 broadly ovate; apex usually slender, straight or slightly curved; 

 margin entire to toothed above; vein extending to the apex or 

 well into the point; cells broad and applied end to end (parencby- 

 matous) toward the base, and narrow, with the ends overlapping 

 (prosenchymatous) toward the apex. 



Habit of flowering. Male and female flowers on separate 

 plants. 



Veil (calyptra). Small and falling early, equal to or shorter 

 than the spore-case, split half the length. 



Spore-case. Cylindrical, unsymmetrical, upright to horizontal, 

 pale yellow-green when young, chestnut when mature; con- 

 stricted under the mouth when dry; neck i to i the length of the 

 spore-case. 



Pedicel (seta). One-half inch to 2 inches long, stout, reddish 

 at the base, pale-yellow or dark throughout. 



Lid (operculum) . Obliquely pointed from a high convex or 

 conical base. 



Annulus. With two to three rows of cells. 



Teeth (peristome) . Cinnamon brown or yellow, paler above, 

 lance-shaped; cilia 2 to 4. 



Spores. Mature in late spring. 



Distribution. Common and widely distributed. 



THE BOAT-HOOK MOSSES 

 HYPNUM: Sub-genus HARPIDIUM, Sulliv. 



The species of the Sub-genus Harpidium are found usually 

 in marshes. They have stems divided irregularly into long 

 ascending rootless branches sometimes plume-like with short 

 branchlets which are all more or less 

 curved at the apex like a boat-hook. 



The leaves are firm and membranous 

 with the apex prolonged into a slender 

 point and turned to one side as a scythe- 

 blade ; a single vein extends to above 

 the middle or to the apex ; the cells are 

 narrow, enlarged and inflated at the 

 basal angles. 

 294 



H. uneinatum. Leaf. 



