No, II.] THE BRYOPHYTES OF CONNECTICUT. 49 



23. Bracts apparently adnata to the base of the perianth.. 



Marsupella, p. 50 

 Bracts entirely free from the perianth 24 



24. Perianth strongly dorsi-ventrally compressed, not plicate 



in upper part Sjcapania, p. 68 



Perianth terete or slightly compressed, more or less plicate 

 in upper part 25 



25. Keels of leaves sharp Diplophylleia, p. 67 



Keels of leaves blunt Sphenolobus, p. 55 



26. Leaves and underleaves with fringed margins 27 



Leaves and underleaves (when present) with entire or 



denticulate margins 28 



27. Plants green, often tinged with brown or red, growing in 



rather dry localities; leaf cells with trigones and a 



smooth cuticle Ptilidium, p. 66 



Plants pale green or yellowish, growing on the ground in 

 swamps; leaf cells thin-walled, with a minutely striolate 

 cuticle Trichocolea, p. 67 



28. Underleaves present 29 



Underleaves none ^3 



29. Underleaves undivided 30 



Underleaves bifid 31 



30. Ventral lobe of leaf not inflated, attached to the stem by 



a narrow base Porella, p. 70 



Ventral lobe of leaf inflated and forming a small water- 

 sac, attached to the stem by a broad base 



Leucolejeunea, p. 72 



31. Ventral lobe of leaf attached to the stem by a broad base, 



forming an inflated water-sac Lejeunea, p. 72 



Ventral lobe of leaf usually forming an inflated water-sac, 

 entirely free from the stem 32 



32. Archegonial branch with one or two subfloral innovations 



Jubula, p. 72 



Archegonial branch without subfloral innovations 



Frullania, p. 7;^ 



33. Dorsal lobes of leaves smooth and entire; perianth dorsi- 



ventrally compressed, truncate at the mouth 



^^ Radula, p. 69 



Dorsal lobes of leaves denticulate and minutely roughened 

 on outer surface by projecting cells; perianth inflated, 

 five-keeled, and contracted at the mouth into a tubular 

 beak Cololejeunea, p. 71 



