JUNGERMANNIACE^. (SCALE-MOSSES.) 709 



apex decurved, more or less denticulate ; lower lobe oblong, obtuse, with an 

 acute tooth at base, longer but narrower than the quadrate underleaves, both 

 with strongly recurved sparsely denticulate margins. (Madotheca Thuja, Du- 

 mort.) — On rocks and trees; more common westward. (Eu.) 



4. P. dent^ta, Lindb. Mostly fuscous-green, irregularly pinnate or sub- 

 dichotomous ; leaves more remote on the branches, obliquely round-ovate, the 

 rounded summit slightly decurved, more or less denticulate ; lower lobe de- 

 current, twisted, obliquely ovate, acute, with recurved undulate denticulate 

 margin and a large acute tooth at base; underleaves twice as wide as the 

 lower lobes, quadrate-oval, the undulate reflexed margin dentate, especially 

 near the base. (Madotheca rivularis, Nees.) — Shaded rocks. Yellow Springs, 

 Ohio {SuUivant). (Eu.) 



5. P. Sullivantii, Underw. Stems strongly decurved at the ends in 

 drying ; leaves suberect, the straight ventral margin strongly involute toward 

 the apex ; cells large, punctate-stelliform ; perianth broadly keeled beneath, 

 the keel 2-angled. (Madotheca Sullivantii, ^msL) — Alleghany Mts. (aSw/Zi- 

 vant) ; rare. 



6. PTILIDIUM, Nees. (ri. 24.) 



Leaves incubous, complicate-bilobed, each lobe divided and lacerately cili- 

 ate ; underleaves 4 - 5-lobed, ciliate. Dioecious. Emit terminating short 

 branches. Involucral leaves 2-4, 4-cleft ; perianth terete, obovate, the mouth 

 conniveut, plicate, denticulate. Calyptra pyriform, coriaceous. Capsule ovate. 

 Spores globose. Antheridia in the base of closely imbricated leaves. (Name 

 a diminutive of irriXov, a feather, from the fringed foliage.) 



1. P. ciliare, Nees. Stems crowded, subpinnate ; fringes of the foliage 

 long-setaceous. (Blepliarozia ciliaris, Dumort.) — On rotten logs and stumps ; 

 common. (Eu.) 



7. TRICHOCOLEA, Dumort. (PI. 24.) 



Leaves succubous, 4-5-divided, and with the underleaves setaceously 

 fringed. Dioecious. Fruit terminal, or axillary from the growth of inno- 

 vations. Involucral leaves coalescent into an oblong truncate hairy tube, 

 blended in our species with the calyptra ; perianth none. Capsule oblong, its 

 pedicel bulbous at base. Elaters free. Antheridia large, in the axils of leavea 

 on terminal branches. (Name from Qpi^, hair, and koAcos, a sheath, from the 

 hairy involucre.) 



1. T. toment611a, Dumort. Stems pinnately decompound, densely 

 tufted, glaucous, 2-6' long ; leaves nearly uniform ; underleaves subquadrate, 

 as wide as the stem. — Among mosses in swamps; common. (Eu.) 



T. Biddlec6mi.e, Aust., very imperfectly described from specimens col- 

 lected in Urbana, Ohio, is said to be simply and rather distantly pinnate. 



8. HERBERT A, S.F.Gray (PI. 24.) 



Leaves large, incubous or nearly transverse, narrow, 3-ranked, the under- 

 leaves being scarcely smaller, cleft to or below the middle, the lobes acute. 

 Dioecious. Fruit terminal on a long branch, Involucral leaves numerous, 

 equitant ; perianth ovate-subulate or narrowly fusiform, 3-angled, deeply 6 - S- 



