MOSSES WITH A HAND-LENS 167 



Leaves compHcate-bilobed, lobes nearly equal or the lower 

 larger giving the appearance of four rows of leaves of 

 which the two upper are incubous and the two lower suc- 

 cubous Scapcuiia. 



Leaves nut complicate-bilobed, in some cases toothed or divided.... 2. 



Leaves entire or slightly emarginate 3. 



Some or usually all of the leaves strongly toothed or lobed 8. 



L^afy stems about J inch wide, leaves oblong, plainly over- 

 lapping; on groiind and over mosses 4. 



Plants about i inch wide, many leaves not overlapping, floating- 

 aquatic Chiloscyphus polyaiifhos var. rivularis. 



Leafy stems j^,. inch wide or less; leaves more nearly circular 6. 



Plants ascending, growing on stones and very wet soli near 



brooks, dark green; leaves round-obovate PlagiochUa. 



Plants closely applied to substratum of rotten wood, humus, 

 or soil, sometimes creeping over other hepatics and mosses; 

 light-green; sometimes turning dark when dried; leaves 

 oblong to oblong-ovate 5, 



Perianth pear-shaped to tubular, abruptly narrqwed to the 



minute opening Jungermannia lanceolata. 



Perianth three-angled, plainly lobed at the top . . . . .^^_^_^_^X7u7ojc3'^/it£.?. 



Leaves plainly margined, apices curved upwards towar3~~?a:cii:— -~__ 

 other when dry 7, 



Leaves not margined, apices reflexed when dry Jamesoniella. 



Leaves not margined, apices curved upwards (incurved), 



when dry Odontoschisma, 



Leaves obliquely attached to the stem, bordered by a single 

 row of very large square cells which are easily seen with 

 high power lens Nardia crcnulata. 



Leaves attached to the stem almost parallel with its long 

 axis, bordered by several rows of denser cells with thicker 

 walls Odontoschismc. 



Upper leaves with a strongly many toothed margin PlagiochUa. 



Leaves 3-5 cleft Loplwzia harhata. 



Leaves two-toothed or cleft 9. 



Plants minute, leafy stems less than nV; inch wide; underleaves 

 absent or so small as to be invisible with a lens; leaves 

 round-ovate to obovate, cleft for at least ^ their length. .Cephalozia. 



(Some small species of Lophozia may be sought here, 

 but their leaves are less deeply cleft and the plants are a 

 much darker green). 



Leafy stems at least ^^ inch wide; leaves two-toothed, but 



scarcely cleft 10. 



Leaves ascending, varying from bidentate to retuse or even 

 entire near apex of stem; leafy stems iV inch or more 

 wide. . . . ' Lophocolea heterophylla. 



Leaves all two-toothed or cleft 11. 



Leaves little longer than broad, concave, ascending \2. 



Leaves much longer than broad, oblong to subrectangular, 



lying flat on the ground; leafy stems at least ^n inch wide 13. 



Leaves subquadrate, inserted crosswise of the stem and sub- 

 clasping Sphenolobus lil tchaii.vii. 



Leaves roundish-ovate, inserted obliquely, not c\as\ying. . .Har pant hits. 



Underleaves so large as to be made out with a lens; perianth 



ascending from end of stem or branch Lophocolea. 



Under leaves small and not discernible with a lens; perianth 



buried in the substratum, attached to the side of the stem. Geocaly.r^ 



