Analytic Keys to the Species of Mosses. 
11 
Basal cells not enlarged. 
Annulus triple ....... H. radicale, 120. 
Annulus simple.H. oigliocladon, 121. 
Leaves not acuminate.H. iiuviatile, 123. 
Costa ceasing above the middle. 
Cells alike throughout. 
Inner perichgetial leaves with a short (i length) point. 
Capsule long cylindric, arcuate, annulus triple . H, serpens, 119. 
Capsule oblong, oblique, annulus simple . H. KocMi Br. & Sch. 1 
Inner perichgetial leaves subuliform-acuminate, cells 
vermicular .H. porpliyrrhizum Lindb. 1 
Cells enlarged, rectangular at basal angles. 
Cilia appendiculate, equalling segments . . H. riparium, 127. 
Cilia rugulose, shorter than segments H. vacillans, 128. 
B. Leaf cells elongated (1:5 or more). 
[Amblystegium spp. especially 127, 128 may be sought here.] 
1. Leaves costate half way or more. 
a. Seta rough. 
i. Leaves deeply plicate lengthwise. 
[Bracliytliecium spp. may be sought here.] 
Plants regularly pinnate. 
Seta scarcely equalling capsule H. Nuttallii, 29. 
Seta longer than capsule. 
Perichgetial leaves coarsely sinuate-dentate, cilia 0 
H. Nevadense, 2 30. 
Perichgetial leaves entire or serrulate. 
Stems erect, stout (to 15 cm.) . . . . H. megaptilum, 34. 
Stems prostrate. 
Leaves with recurved, spinulose teeth . H. liamatidens, 3 . 
Leaves serrulate. 
Capsule oblong .... H. pinnatifidum, 31. 
Capsule long cylindric .... H„ Amesioe, 4 . 
Plants irregularly branched. 
Leaves ovate-lanceolate (1:3) cilia 3, long as segments H. seneum, 28. 
Leaves long-lanceolate (1:5) cilia 1 or 2, long or short H. lutescens, 27. 
1 Renauld & Cardot: Bot. Gaz., xiv (1889), 99. 
2 Hovialothecium Nevadense Ren. & Card.: Bot. Gaz., xiii (1888), 202. 
3 Kindberg: Bull. Torr. Bot. Club, xvi (1889), 97. 
4 Renauld and Cardot: Bot. Gaz., xiii (1888), 202, pi. XX. 
