686 IIKPATIC/E. (LIVERWORTS.) 



SUBORDER III. MARCHANTIACE^E. 



Frondose and terrestrial perennials, furnished beneath with imbricating 

 colored scales, and numerous tubular radicels tuberculate within ; recepta- 

 cle raised on a peduncle springing from the apex of the frond (also from 

 the back, in No. 12), capitate or radiate, bearing from the under side pen- 

 dent calyptrate capsules which open variously, but are not regularly 

 4-valved : elaters with two spiral fibres. 



5. MARC II ANT I A, L. BROOK-LIVERWORT. (Tab. 20.) 



Fertile receptacle radiated. Involucres alternate with the rays, 2-valved, 

 lacerate; enclosing 3 - 6 one-fruited 4-5-cleft perianths. Calyptra opening at 

 the apex, persistent. Capsule globular, pendulous, exsertly pedicelled, dehiscing 

 at the apex by several re volute segments. Spores smooth. Elaters long, slen- 

 der, and attenuated at each end. Inflorescence dioecious. Sterile receptacle 

 peduncled, shield-like, lobed or rayed, papillose on the upper sin-face by the sum- 

 mits of the immersed antheridia. Lentil-shaped gemma in cup-like receptacles 

 on the back of the frond. Frond expanded, forking, with a broad diffused mid- 

 rib. (Named after Nicholas Marchant, a French botanist.) 



1. M. poly Ill6 rplm, L. Fertile receptacle deeply divided in a star-like 

 manner; the rays 8-10, terete. Shaded and moist places; very common. 

 (Tab. 20.) (Eu.) 



2. UI. disjuincta, Sulliv. (Mem. Amer. Acad. 1. c. p. 63, t. 3.) Fertile 

 receptacle |-circular, radiately 7 - 9-lobed ; the lobes cuneate, crenulate on the 

 outer margin; sterile receptacle digitately lobed: about the size of No. 1. 

 Springy places, banks of the Alabama River, near Clairbourne : fruiting in May. 



6. PREISS1A, Nees. (Tab. 20.) 



Fertile receptacle hemispherical, 2-4-lobed, with as many rib-like rays alter- 

 nating with and shorter than the lobes. Involucres attached to the under side of 

 the lobes, 1 -3-fruited, opening beneath by an irregular line. Perianth obconic- 

 campanulate, angular, unequally 4-5-lobed. Calyptra persistent, opening ob- 

 liquely. Capsule large, pedicelled, dehiscing by 4 - 5 revolute segments. Spores 

 tuberculate. Elaters short. Inflorescence dioecious, rarely monoecious. An- 

 theridia immersed in a peduncled peltate receptacle. Frond sparingly forked, 

 increasing by joints from the apex. (Named for L. Preiss, a German botanist.) 



1. P. com ill lit is ta, Nees. Fertile receptacle somewhat angled by the 

 prominent keel-like rays ; capsule conspicuous, dark purple. Shaded, moist 

 places, Niagara Falls (Carey), Lake Superior (Loring), &c. (Tab. 20.) (Eu.) 



7. DUUIORTIERA, Nees. HAIRY LIVERWORT. (Tab. 20.) 



Fertile receptacle convex, 2-8-lobed. Involucre 1-fruited, opposite to and 

 connate with the lower surface of the lobes, horizontal, oblong, opening by a 

 vertical slit at the outer extremity. Perianth none. Calyptra obovate, rupturing 



