222 BULLETIN OF THE UNIVERSITY OF WISCONSIN. 



Lamellaa 9-13 cells high A. Selwyni, 256. 



Lamellae 4-8, serrate A. Lescnrii, 257. 



Lamellae 1-3, 1-3 cells high, lamina smooth . A. crispum, 257. 



Leaves not margined. 

 Costa lamellose on both sides . . . .A. parallelum, 258. 

 Costa lamellose on upper side only ... A. leiophyllnm, S61, 

 Costa nearly smooth A. rosniatnm, SGZ. 



OLIGOTRICHUM, p. 258. 



Costa lamellose on both surfaces. 



Capsule rough when dry, leaf margin plane . 0. aligernm, 258. 



Capsule furrowed when dry, leaves nearly tubular by 



the incurved margin .... 0. hercynicnm,^ S6S. 



Costa only lamellose on upper surface ... 0. Lyallii, 259. 



POGONATUM, p. 260. 



I. Plants simple, mostly short, leaves straight when dry. 



[P. alpinuTti simplex will be sought here.] 



Lamellae with marginal cells smooth. 

 Leaves entire ...... P. bractayphyllnm, 261. 



Leaves serrate ...... P. brevicaule, 260. 



Lamellae with marginal cells papillose. 

 Teeth of leaves very long, often refiexed, marginal cells 



of lamellae subquadrate .... P. dentatum, 261. 



Teeth moderate, 2 rows of marginal cells of lamellas 



transversely rectangular .... P. capillare, 261. 



II. Plants large {4-15 cm.), leaves twisted when dry. (Ill) 



Leaves strongly contorted when dry, lamellae 20-30. 

 Less than 1 cm. long, short sheathing, capsule smooth. 

 Leaves scarcely enlarged at the base, acute P. contortum, 262. 

 Leaves enlarged at the base, abruptly pointed P. atrovirens, 262. 

 More than 1 cm. long, not sheathing, capsule pap- 

 illose P. erythrodontium, 365. 



Leaves spreading or patulose when dry, lamellae 



about 60 P. Macounii, 567. 



> See Appendix, no. 361, 



