Wisconsin Academy of Sciences , Arts and Letters. 
2. Leaves not papillose. 
a. Shortly bicostate. 
Stem-leaves filiform-pointed.H. procurrens, 5. 
Stem-leaves not filiform-pointed. 
Obscurely denticulate at apex ... H. leucocladulum, 25. 
Distinctly denticulate all around H. compressulum, 26. 
1). XJnicostate or ecostate. 
i. Paraphyllia numerous, eiliate H. pahulosiim, 24. 
ii. Paraphyllia 0. 
■x- Leaves coarsely serrate, plants dendroid. 
Branch leaves apparently 2-ranked, complanate . H. Bigelovii, 97. 
Branch leaves equally spreading. 
Perichaetial leaves reflexed, dioicous. 
Cilia of endostome equalling teeth H. Leiherg’ii h 
Cilia short. H. neckeroides, 96. 
Perichaetial leaves erect, heteroicous . . H. Allegiianiense, 95. 
* * Leaves entire, plants creeping. 
Ecostate or with obscure traces of a nerve. 
Cilia 0. 
Capsule constricted under mouth when dry 
Capsule not constricted 
Cilia 1—2. 
Plants minute, filiform. 
Leaves ovate, long acuminate 
Leaves long-lanceolate . . . . 
Plants large, in wide flat mats 
H. subtile, 117. 
H. Sprucei, 116. 
H. conferyoides, 118. 
H. inimitissiinum, 115. 
H. adnatum, 124. 
Costate. 
-8-*- Leaves bordered with 4—5 rows of linear cells H. Lescurii, 126. 
-i —s- -e-e- Leaves not bordered. 
= Plants in compact tufts 2—3 cm. deep . . H. compaction, 125. 
= == Plants in loose mats or tufts. 
Tf Costate to apex. 
Leaves acuminate. 
Basal cells much enlarged . . . . H. irriguum, 122. 
1 Britton: Bull. Torr. Bot. Club, xvi (1889), 111. 
