385 
Leaves not specially narrowed above the base. 
Perianth linear-fusiform, widest below the middle; dioi- 
cous, 4. C. catenulata. 
Perianth linear-clavate, widest above the middle; dioicous 
or autoicous. 5. C. Virginiana, 
Leaves medium size, 0,5~0.65 mm. long; leaf-cells 40-50 x. 
Leaves longer than broad, cleft half way to the base or more; per- 
ianth thin. 
Smaller; leaves 0.5 mm. or less long; usually monoicous. 
6. C. bicuspidata, 
Larger; leaves 0,65 long with apiculate divisions; dioicous, 
7. C. extensa. 
Leaves as broad or broader than long; monoicous; perianth fleshy, 
usually narrowed at base. 8. C. pleniceps. 
Leaves larger, 1-1,35 mm, long, usually narrowed at base; plant semi- 
aquatic, 9g. C. fluttans, 
Leaves only about the width of the stem or even narrower; innermost 
involucral leaves united into a cup. § CEPHALOZIELLA. 
Plants small; stems 2-4 mm. long. : 
Perianth linear or narrowly fusiform, the mouth denticulate or 
lo. C. divaricata, 
nearly entire. 
11. C, Macouniz. 
Perianth ovate-fusiform, the mouth ciliate. 
Plants minute ; stems less than 2 mm. long. 
Underleaves lanceolate, entire, often present only near the end of 
the stem. 12. C, Sullivantii, 
Underleaves everywhere present, the upper ones bifid. 
13. C. minima, 
Branching lateral ; leaves bifid with dentate margins; perianth terminal; under- 
§ PRIONOLOBUS. 
leaves usually present. 
14. C. Turneri. 
Leaves complicate-bifid, equitant, 
1. CEPHALOZIA CURVIFOLIA (Dicks.) Dumort. Recueil d’ Obs. sur 
les Jung. 18. 1835. 
Jungermannia curvifolia Dicks. Pl. Crypt. Brit. 2: 15. pl. 5,f. 
7: 1790. 
Nowellia curvifolia Mitt. in Godman, Nat. His. Acores, 321. 
1870, : 
Gametophyte a green or reddish slender creeping leafy axis, 
Sparingly branching; leaves somewhat orbicular, deeply concave, 
with two slender incurved teeth widely separated at base and soon 
becoming one cell wide; underleaves wanting ; leaf cells isodia- 
Metric, 20-25 » in diameter: monoicous or dioicous ; perianth on 
@ short branch, triangular-prismatic, about 1.3 mm. long, plicate, 
with the mouth constricted and short ciliate; involucral leaves in ‘ele 
two or three rows, deeply bifid with broad serrulate divisions. 
