190 BULLETIN OF THE UNIVERSITY OP WISCONSIN. 



TRICHOSTOMUM, p. io8. 



I. Lamina composed of one layer of cells, papillose. 



Margin reflexed or undulate, entire. 



Annulus wanting T. tophaceum, 109. 



Annulus large, compound .... T. pyriforme, 109. 



Margin plane or incurved. 

 Costa reaching apex or excurrent; serrate above. 

 Base of leaf yellowish, with thick walled rectangular 



cells T. crispalnm, 109. 



Base of leaf hyaline. 

 Abruptly mucronate or obtuse, with long papillae T. flavo-virens, 109. 

 Gradually acuminate, papillae low . . . T. nitidnm, 118. 

 Costa ceasing far below apex; entire . . T. Coloradense, 413. 



II. Lam.ina of two layers, upper surface mam.illose, lower smooth. 



Costa excurrent, leaves denticulate above . T. Tancouveriense, 119. 

 Costa percurrent or vanishing below apex, serrate above. 



Peristome not twisted, seta arcuate or variously bent T. flexipes, 110. 



Peristome twisted, seta subflexuous . . . T. anomalum, 110. 



DESMATODON, p. no. 



I. Capsule erect or nearly so. 



A. Leaves without a hyaline or thickened border. 



I. Costa excurrent into a hair. 



a. Papillose. 



Capsule oblong (1:2 or 1:3 excl. lid), 16 teeth divided nearly or quite to 

 base. 

 Plants of mountainous regions; calyptra reaching base 



of capsule D. latifolius, 111. 



Plants of lowlands; calyptra reaching half way to base 



of capsule D. Guepini, 114. 



Capsule cylindric (1 :5-6); teeth divided half way or entire. 



[D. obliquus may be sought here.] 



Dioicous D. plinthobius, 112. 



Monoicous D. Neo-Mexicanus, 113. 



