'74 
Wisconsin Academy of Sciences, Arts and Letters. 
Leaves spreading every way. 
Ovate, acute, rarely slender-pointed; in water . H. rusciforme, 90. 
Deltoid, with long slender points. 
Points twisted, plants golden yellow ... H, Boscii, 72. 
Points straight. 
Spreading, branchlets attenuate H. strigosum, 70. 
Appressed, branchlets short, julaceous . H. diversifolium, 71. 
ii. Lid convex to conic. 
* Leaves acute or acuminate, serrulate. 
Primary branches erect, dendroid to fasciculate, capsule symmetric , sub¬ 
erect or inclined. 
•*—e- Leaves papillose on bach. 
In compact tufts, dark green, branchlets not attenuate 
II. Brewerianimi, 66. 
In loose tufts, branchlets attenuate, stoloniferous. 
Cilia solitary, margin of stem leaves reflexed . H. spiculiferum, 64. 
Cilia 2—3, margin of stem leaves not reflexed . H. stoloniferum, 63. 
+-*• Leaves smooth. 
Capsule cylindrical, cilia solitary, £ segments . H. aggregating, 67. 
Capsule oval-oblong, cilia 2—3. 
Perichsetial leaves serrate .... H. myosuroides, 62. 
Perichsetial leaves entire.H. aeuticuspis, 65. 
Primary branching irregular or pinnate, capsule unsymmet- 
tric , subarcuate, horizontal (excl. 36 and 44). 
Capsule symmetric, erect. 
Synoicous, small (branches 1 cm. long) . . . H. Utaliense, 44. 
Dioicous, large (branches 3—4 cm.) . . H„ acuminatum, 36. 
Capsule unsymmetric, inclined. 
In loose tufts, plants stout or long. * 
Leaves narrowed from lower third to apex, usually 
whitish or yellowish. 
Capsule short (1; 1.5), monoicous, leaves straight 
when dry.H. salebrosum, 37. 
Capsule short (1:1.5—2), dioicous, leaves twisted- 
flexuous when dry. H. Tliedenii, 41. 
Capsule longer (1:3), dioicous, leaves straight when 
dry.H. laeturn, 35. 
Leaves narrowed from base to apex, bright green, 
H. acutum, 38. 
monoicous 
