26 A MANUAL OF MOSSES 



four layers of thin-walled, large, fibrillose, and porose cells, 

 the innermost largest; stem-leaves about 1-1.8 iVim. long, 

 widely and bluntly Ungulate, somewhat concave, the upper 

 half rounded and with an erose-fimbriate margin, the base 

 more or less auriculate; hyaline cells of stem-leaves usually 

 non-fibrillose and non-porose, a few often septate, the upper 

 median more or less rounded-hexagonal, the basal elongate, 

 the insertion-cells small and brownish-incrassate ; branches 

 usually four, two or three spreading, tumid, about 1.5 cm. 

 long, the rather shortly tapering apex pendent, the comal 

 branches short and more or less erect-spreading, often obtuse, 

 the pendent branches closely applied to the stem, very slender ; 

 bianch-leaves 2-3 mm. long, broadly ovate, very concave, the 

 margins involute, the apex abruptly and bluntly tapering, 

 cucullate and more or less widely squarrose-spreading ; the 

 hyaline cells of the branch-leaves broad, fibrillose, ventrally 

 with a few large round median pores, with small pores in the 

 angles, dorsally with large round or elliptic pores at the cell- 

 angles, the large pores usually equalling about one-third the 

 width of the hyaline cell ; the basal hyaline cells of the branch- 

 leaves are distinctly comb-fibrillose on the inner lateral side of 

 the wall adjoining the chlorophyllose cells; in cross-section 

 the chlorophyllose cells are widely trapezoidal, the ventral wall 

 widest and almost or quite as wide as the lateral walls, the 

 dorsal wall exposed between the highly convex dorsal walls 

 of the hyaline cells and usually one-third to one-half the width 

 of the lateral wall ; the cuticular sheath of the branches con- 

 sisting of one layer of rectangular, fibrillose, porose cells : fruit 

 not seen, but spores of S. imbricatum are stated to be yellowish, 

 smooth, and about .025 mm. in diameter. 



This variety is probably well distributed in regions where 

 the typical form occurs. 



Crawford: Pymatuning Swamp, near Linesville, May 12, 

 1908. O. E. J. (Figured.) 



Mercer : Near Houston Junction, July 12, 1902. J. A. S. 



2. Sphagnum affine Renauld and Cardot. 



(S. imbricatum var. affine Warnstorf.) 

 (Plate I) 



Densely cespitose, usually bluish or glaucous-green above 

 and more or less yellowish below : stems robust, sometimes as 

 much as a decimeter in length, usually much less, densely 

 branched; cuticular sheath distinct, three-layered, the inner 

 layer with the largest cells, the outer cells usually densely 

 spirally fibrillose and 2-6-pored ; stem-leaves large, 1.6-2.2 

 mm. long, about two-thirds as wide, widely spatulate, the 

 rounded upper half somewhat concave, erose-fimbriate ; hyaline 



