42 American Midland Naturalist Monograph No. 6 



24a. Sphagnum acutifolium var. viride Warnstorff 



(S. capillifolium var. viride Jennings) 

 Plate V 



Rather densely cespitose, low, yellowish above, greenish to yellowish-green 

 below, lacking the reddish tinges so often characteristic of the species: stems 

 slender, in our region usually 5-8 cm long, in cross-section showing a yellov/ish 

 wood-cylinder and a distinct cuticular sheath of 2-4 layers of large but non- 

 porose cells; stem-leaves oval-triangular to lingulate-triangular, 1-2 mm long, 

 always widest at the base, towards the apex abruptly narrowed to a truncate 

 apex with a few teeth, the upper margin usually somewhat involute, the margin 

 narrowly hyaline-bordered, the border sometimes wider at the base; hyaline 

 cells of stem-leaves largely once-septate, especially below the middle, those of 

 the upper half of the leaf usually more or less completely fibrillose and some- 

 times distinctly laterally porose; branches fairly numerous, usually in fascicles 

 of four, two spreading-recurved and two appressed-pendent and very slender; 

 the cuticular sheath of branches composed of cells with a distinct neck and 

 terminal pore; branch-leaves 1-2 mm long, ovate-lanceolate, when dry hardly 

 secund but with slightly spreading tips, concave, with involute margins above, 

 uniformly narrowly hyaline-bordered, the narrow apex somewhat erose-dentate; 

 hyaline cells of branch-leaves rather slender, abruptly fibrillose, with small 

 somewhat elliptic pores at the cell-angles, sometimes also lateral pores of a 

 similar character between the angle-pores on both sides of the leaf, while towards 

 the margin of the leaf the pores are often larger and more numerous; in cross- 

 section the chlorophyllose cells are more or less trapezoidal, unusually short, 

 free on both surfaces but the hyaline cells projecting far beyond them both 

 ventrally and dorsally, especially dorsally; perichaetial leaves said to be very 

 large and broadly ovate: spores yellow, smoothish. 



In cool, boggy situations in Europe, Asia, South America, and in the 

 regions of the South Pacific. In North America extending from Greenland 

 and Alaska south to Virginia, Pennsylvania, and Wisconsin. 



Butler Co.: In boggy place in upland pasture 1 mi. n. of Smith School, Parker 

 Twp. Adam M. Barker. July 5, 1935. Fayette Co.: In hollows along rocky river-bed 

 above the falls, Ohio Pyle, July 4, 1908. O.E.J, (figured) 



Order II. Andreaeales 



Small, monoicous (or dioicous), dark brown to almost black, when dry 

 very brittle, mostly cespitose on granite or slate rocks : stems slender, radiculose 

 below, dichotomous, with fascicled branchlets, no central strand; leaves small, 

 crowded, erect-spreading to often falcate-secund, uni-stratose to partly bi- 

 stratose, thickish, often more or less papillose, costate to ecostate, very opaque; 

 cells small, incrassate: seta none, but represented by a pseudopodium from the 

 gametophore; capsule oval, opening by 4 (-8) vertical slits, the valves remain- 

 ing united both above and below; spores and columella derived from the en- 

 dothecium; no air-cavity between the spore-sac and the capsule-wall; calyptra 

 torn at the base, delicate; spores large, about .034 mm in diameter, chlorophyl- 

 lose. 



