32 American Midland Naturalist Monograph No. 6 



less undulate, loosely imbricate, with widely spreading or recurved tips; hyaline 

 cells of branch-leaves narrow, fibrillose, ventrally with rounded medium-sized 

 pores in the cell-angles, dorsally with single smaller round pores in the cell- 

 angles or sometimes in rows laterally; in cross-section the chlorophyllose 

 cells triangular and only dorsally exposed, or more usually trapezoidal and 

 free on both faces, the dorsal face wider, the hyaline cells more convex ven- 

 trally: fruit not seen. 



In bogs, swamps, etc., probably widely distributed. In North America 

 extending from the Arctic south to northern United States. 



In o-.ir region known from one locality. Blair Co.: Springy mountain slop>e, Rhodo- 

 dendron Park, Llyodsville, October 18, 1901. J.A.S. (figured). 



11. Sphagnum cuspidatum Ehrhart 



{S. virginianum Warnstorf) 

 Plate IV 



Usually pale and slender messes of wet bogs or often submerged in pools. 

 Stem with 2 or 3 layers of non-porose, non-fibrillose, large and thin-walled 

 cortical cells clearly distinct from the wood-cylinder. Stem-leaves isosceles- 

 triangular, about 1-1.4 mm long and about 0.6-1.1 wide, inrolled above, slightly 

 toothed at the narrow truncate tip; the border strong, considerably widened 

 below; the hyaline cells fibrillose and porose. Branches usually 4, two of them 

 drooping or slightly spreading, the other two spreading linear-lanceolate to 

 elongated-lanceolate, about 1.5-3 mm long, the tip toothed, often falcate- 

 secund, the leaves often undulate when dry; the border of 2-4 (3-8) rows of 

 linear cells. Hyaline cells ranging from the basal linear-rhomboidal cells 

 about 15 times as long as wide upwards to those only about 5 times as long 

 as wide, all fibrillose and somewhat porose. Chlorophyllose cells trapezoidal 

 to 4-sided, both surfaces free, but the dorsal (abaxial) surface wider. 



In wet bogs and pools, often submerged, Eurasia and from Georgia to 



Newfoundland. 



Allegheny Co.: On springy hillside about one mile west of Thornburg, July 12, 

 1922. Mrs. Alice B. Lord (figured). 



Subsection V. Subsecunda 



A difficult group of diverse forms. Branch-leaves mostly more or less 



s.^cund, the pores of their hyaline cells mostly small and numerous, their 



chlorophyllose cells truncately elliptic or trapezoidal, mostly central and ex- 

 posed on both surfaces. 



12. Sphagnum contortum Schultz* 



(S. subsecundum var. contortum Huebener; S. laricinum Spruce) 

 Loosely cespitose, green to brownish or yellowish, sometimes more or less 



* Andrews, A. L. (N. Am. Flora 15: 21-22. 1913) treats S. contortum, S. platy- 

 phyllum, S. auriculdtum, S. subsecundum, and S. inundatum as being a single polymor- 

 phic species, S. subsecundum. 



