Jennings: Manual of Mosses — 29. Leskeaceae 213 



6. Thuidium Philiberti Limpricht 



(Thiddium intermedium Philibert, not Mitten) 



Grout (Moss Flora) regards this as "A poorly delimited subspecies of T. 

 delicatulnni." Stems to 12 cm or more, bi- to tri-pinnate; branches up to 1 

 cm; stem leaves cordate-lanceolate, narrowed into a filiform acumination of a 

 single row of 3-8 linear cells, about 1.5-1.8 mm by 0.6 mm; costa strong ending 

 at or in the long acumination; median cells incrassate, roundish-oval, towards 

 th basal margin much more rectangular; branch-leaves ovate, acuminate, about 

 0.6 mm long by 0.4 mm wide, margins plane, apical cell with 2 or 3 points; 

 inner perichaetial leaves with the slender acumination about three times the 

 length of the body of the leaf mostly without cilia; seta 1.5-2.5 cm long; 

 capsule inclined, curved, cylindric, about 3 mm by 0.8 mm, castaneous; lid 

 cbliquely-rostrate; spores ripe in fall and winter. 



In wet swampy situations on ground or bases of trees. New Jersey, Penn- 

 sylvania, and in the West. Not yet known from our region. 



7. Thuidium delicatulum [Linnaeus] Mitten 

 Common Fern Moss 



Plate XL 



The "Common Fern Moss." — Bright green above, darker below, large, 

 forming rather large and intricately woven mats, when dry rather stiff and 

 harsh; stems elongate, procumbent or arched and alternately rooting, often 

 reaching a length of 10 or 12 cm; the branching is twice or thrice pinnate, 

 very regular and fern-like; stem-leaves triangular-ovate, somewhat cordate, 

 gradually acuminate, about 1 m.m long, erect-spreading, appressed when dry. 

 somewhat serrate and marginally m.ore or less recurved; leaf-cells uni-papillate 

 on both rides, rather incrassate, the median quadrate-oblong to rhombic-oval 

 or rounded-quadrate, about .007 to .008 mm across; costa strong and ending 

 in the acumen; branch-leaves much smaller, broadly ovate, acuminate, the 

 apical cells with 2 (to 4) papillae, usually appearing bifid; inner perichaetial 

 bracts with a very few, filiform, articulate cilia on the margins: seta about 2 

 to 3 cm long, rather stiff, richly castaneous, somewhat dextrorse; capsule large, 

 the urn about 3.5 to 4 mm long, strongly inclined to horizontal, arcuate, nar- 

 rowly oblong, yellowish to castaneous; lid slenderly conic-rostrate, about 1.5 

 mm long; annulus narrow, usually 2-seriate; peristome large, reddish, the teeth 

 strongly and numerously trabeculate, often split at the hyaline and papillose 

 apex, dorsally cross-striate below, the divisural and lamellae distinct; segments 

 about as long as teeth, carinately split, papillose above; the 2 or 3 slender 

 nodose cilia rising from a basal membrane about one-third as high as the 

 peristome; spores rather thin-walled, pale-castaneous, very slightly roughened, 

 about .014-. 017 mm, mature in winter. 



On the ground, stones rotten wood, stumps, etc.; in moist woods; Europe, 



Asia, and from Labrador to the Rocky Mountains and south to the West 



Indies and South America. Very common in the woods of our region. 



Known from 18 coiintieri in western Pennsylvania, and probably occurs in all. Speci- 

 men figured: Power's Run, Allegheny Co., Sept. 14, 1905. O.E.J, and G.K.J. 



