122 A iJANUAL OF MOSSES 



thin-walled, rectangular to quadrate cells : capsule erect, ex- 

 serted, S3mmetric, 8-plicate when dry, stomata superficial ; 

 annulus persisting; peristome mostly double, segments usually 

 8, rarely 16 or none ; lid convex or conic, rostrate ; calyptra 

 mitrate, with 10-16 obtuse folds, incised-lobed at base, hirsute 

 with shining golden-yellow hairs or rarely almost glabrous. 



A world-wide genus of about 50 species, most numerous 

 in America; in North America 16 species; in our region three 

 species. 



Key to the Species. 



a. Rupestral; leaves not crispate when dry. i. U. ainericana. 

 a. Arboreal: leaves more or less crispate when dry. 



b. 

 b. Capsule smooth, slightly plicate below the distinctly narrowed 



mouth. 2. U. ludwigii. 



b. Capsule wide-mouthed, distinctly plicate. 



c. 

 c. Capsule constricted below the mouth, gradually narrowed at base 



to the long neck: teeth confluent. 3. U. crispa. 



1-. Capsule not distinctly constricted below the mouth, abruptly nar- 

 rowed to the shorter neck; teeth separated at apex. 



3a. U. crispa var. minus. 



1. Ulota americana [Beauvois] Limpricht, not Alitten. 

 {U. hutchinsiae Hammar). 

 (Plate XV) 

 Rather loosely cespitose, blackish with greenish tips, about 

 1 cm. high, or less : stems creeping, sparingly branched with 

 erect branches, when dry the leaves appressed and straight; 

 leaves often with hair-like paraphyllia at base, lance-ovate or 

 linear-lanceolate from an ovate base, carinate, concave at 

 least below, margins usually revolute in lower half, costa and 

 base of lamina pellucid-castaneous, apex sub-acute; costa 

 strong, sometimes percurrent; apical and median leaf-cells 

 incrassate, papillose, rounded-quadrate, rather opaque, the 

 basal marginal rounded-quadrate to rounded-rectangular, hya- 

 line, towards the costa becoming linear, more or less vermicu- 

 lar and occasionally anastomosing, much incrassate and 

 markedly pellucid-castaneous : seta about 2 mm. long, smooth, 

 with a distinct smooth volva at base ; capsule yellowish, cylin- 

 dric-oblong, basally tapering, when dry 8-costate and with 

 more or less distinct intermediate costas at mouth, the neck 

 and seta decidedly dextrorse ; stomata immersed ; peristome- 

 teeth 16, more or less paired, articulate, granular, when dry 

 strongly reflexed, segments 8, about one-half as high, bi- 

 seriate below; calyptra yellowish, mitrate, plicate, incised- 

 lobate at base, densely clothed with erect to spreading slender 

 hairs; lid conic-rostrate; spores globose, papillose, incrassate, 

 about .016-.018 mm., mature in spring. 



