148 A MANUAL OF MOSSES 



Key to the Species. 



a. Leaves distinctly bordered. b. 



a. Leaves not distinctly bordered, at least not above. 



i. 

 b. Costa vanishing below the apex. 9. B. capillare. 



b. Costa percurrent to long-excurrent. c. 

 c. Leaves long-decurrent; costa short-excurrent. 



d. 

 r. Leaves short- or non-decurrent; costa long-excurrent. 



d. Synoicous. i b. bimum. 



d. Dioicous. 2. B. pseudotriquetrum. 



e. 1 enstome-teeth with the trabeculse connected by various cross- 

 partitions. 1. B. cernuum. 



e Feristome-teeth with trabecule unconnected. 



f. Autoicous; antheridia at apex of lateral innovations. 



. 6. B. pallcscens. 



t. Dioicous. g. 



f. Synoicous. h. 



g. Leaves ovate-lanceolate with rhomboidal cells. 



7. B. caespiticiuiii. 

 g. Leaves rounded to wide-obovate; cells short-hexagonal. 



9. B. capillare. 

 h. Leaves non-dccurrent; spores about .025 mm. 



5. B. intermedium. 

 h. Leaves shortly decurrent; spores about .010 — .014 mm. 



4. B. afUne. 

 i. Costa long-excurrent. S. B. intermedium. 



i. Costa vanishing a little above middle of leaf. 



8. B. argentcum. 



1. Bryum cemuum [Hornschuch] Bryologia Europjea. 

 {B. pendulum Schimper; Cynontodiniii ccrnmim Hedwig). 

 (Plate XVIII) 

 Densely ces'i)itose, usually darkish-green : steijis in our 

 region short, about 6-9 mm., erect, sparsely branched, matted 

 below with a castaneous tomentum, stem reddish ; leaves rather 

 lax, somewhat tufted, close, erect-spreading, ovate-lanceolate, 

 long-cuspidate-acuminate, more of less recurved on the bor- 

 ders, reddish at base, usually obscurely denticulate at apex, 

 when dry rigid, shrunken and somewhat twisted; costa stout, 

 reddish, long-excurrent ; leaf-cells rather small, rhoinboidal to 

 somewhat elongate above, at base thin-walled, rather in- 

 flated, rectangular, at margin linear-prosenchymatous .in 2-A 

 rows, forming a strong border : seta usually 3-4 cm. long, slen- 

 der, flexuous, lustrous, castaneous; capsule pendulous, elongate 

 oval-pyriform, usually 4—5 mm. long, tapering below into a neck 

 about 1.5 mm. long, brownish, hardly contracted below the 

 mouth except when dried prematurely ; annulus 2-3-seriate, 

 revoluble ; operciilum rather small, conic-apiculate ; peristome- 

 teeth linear-triangular, yellowish-pellucid below, sub-hyaline 

 and papillose above, strongly trabeculate and with prominent 



