3'4 
The Ohio Naturalist. 
[Vol. V, No. 6, 
IS. Leaves comj)licate-bilobcd. 19. 
Leaves not complicate-bilobed. 20. 
19. Perianth oval, scarcely or not compressed, plicate; mouth denticu- 
late. Diplophylltini. 
Perianth dorsally compressed, mouth truncate, bilabiate, decurved. 
Scapania. 
20. Ujiderleaves present (Plagiochila and Cephalozia may be sought 
here). 21. 
L’nderleaves none or usually none. (Odontoschisma may be sought 
here). 2(1. 
21. Leaves bilobed, bidentate or ernarginate. 22. 
Leaves entire (sometimes retuse). 2.5. 
22. Leaves ernarginate; perianth connate with the calyptra. Harpauthus. 
Leaves bilobed or Ihdentate; perianth free. 25. 
25. L’nderkaves 2-4-cleft or parted. Lophocolea. 
Underleaves entire or nearly so. 24. 
24. Involucral leaves 2, connate at base, entire. Stems without runners. 
Leaf-cells roundish, 5-7-angular, cell walls much thickened, each 
cell appearing as if surrounded by about (1 smaller, 5 (or more)- 
angular ones. Mylia. 
Involucral leaves 5-ranked, bifid or bilobed. Stems with runners. 
Leaf cells round, surrounded by much thickened walls. 
Odontoschisma. 
2.5. L^nderleaves 2-4-parted. Chiloscyphiis. 
Lmderleaves subulate, fugacious. J iingermannia. 
2(1. Leaves bifid or bilobed. 27. 
Leaves entire (sometimes retuse) or spinulose-dentate. 28. 
27. Perianth triangular .prismatic, the contracted mouth dentate. 
C ephalozia. 
Perianth oval-oblong, plicate, mouth denticulate. Jungermannia. 
28. Leaves entire (sometimes retuse). 29. 
Leaves spuinlose-dentate, rarely entire, the dorsal margin refle.xed; 
perianth compressed. Plagiochila. 
29. Perianth cylindrical, wider above, truncate, depressed, with orifice 
prominently umbilicate, ciliolate, Liochlacna. 
Perianth compressed or terete, usually carinate, mouth entire or 
toothed. J Iingermannia. 
50. Capsule splitting into 4 regular valves (Jungermanniaceae). 51. 
Capsule not splitting into 4 regular valves. 5.5. 
51. Thallus with distinct costa. 52. 
Thallus with indistinct costa or none. 54. 
52. Thallus villous throughout or hairy (ciliate) on marign and midrib 
beneath. Metzgcria. 
Thallus smooth. 55. 
35. Perianth long tubular; thallus mostly simjde with sinuate or undulate 
margins, transparent, without inside cavities. Pallavicinia. 
Perianth none; thallus dichotomous or radiate with pinnatifid mar- 
gins, opaque, with inside cavities filled with green cells. Blasia. 
54. Thallus mostly simjde or forked, with thick margin. Sporogonium 
rising from the underside near margin. Elaters persistent on tip 
of valves. Ancnra. 
Thallus mostly palmatifid or pinnately lobcd with thin margin (one 
layer of cells). Sporogonium rising from the upper surface. 
Elaters persistent in the centre of the capsule. Pcllia. 
35. Capsules solitary, more or less perfectly 2-valved (sometimes rup- 
turing irregularly), linear (Anthocerotaceae). 3(1. 
Capsules aggregate, pendant from the underside of a peduncled disk 
or cruciately arranged in 4 horizontal segments or sessile on the 
thallus or immersed in it. 37. 
