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 (parenchy- 

 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 | to J 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. 



Teeih (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 



H.uncinatum. Leaf. basal angles. 



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