HEPATIC-E. (liverworts.) 685 



3. AlVTHdCERO§, Mich. Horned Liverwort. (Tab. 20.) 



Involucre tubular. Calyptra conical, with a subsessile stigma. Capsule 

 narrowly linear, siliquarform, 2-valved, exsertly pedicelled. Spores niuriculate. 

 Elaters flexuous, the spiral fibres imperfect or none. Inflorescence monoecious : 

 antheridia dorsal, sessile in a cup-shaped involucre. — Frond orbicular-radiate, 

 lacerate, with immersed gemmae as in Notothylas. (Name formed of avdos, 

 a blossom, and Kepas, a horn ; from the shape of the involucre.) 



1. A. pi&HCtatitS, L. Frond deep green, 5" -8" in diameter, margins 

 plicate, crenate, the surface papulose-reticulated ; involucre erect, cylindrical, 

 with a scarious and obliquely truncate mouth. — Wet slopes, sides of ditches, 

 &c. (Eu.) 



2. A. IffeviS, L. Larger than the preceding species ; surface of frond 

 smooth ; mouth of the involucre more broadly scarious. — In similar places. 

 (Tab. VI.) (Eu.) 



3. A. lacitiiatUS, Schwein. A still larger species ; the frond more la- 

 ciniated, its surface smooth : distinguished from No. 1 and 2 mainly by tho 

 bilobed mouth of its involucre. — Wet gravelly places, Southern States : form- 

 ing patches a foot or more in diameter. 



4. KOTOTH¥LAS, Sulliv. (Tab. 20.) 



Involucre a profusion of a portion of the upper stratum of the frond, opening 

 irregularly at the apex. Calyptra vanishing early. Capsule closely invested 

 by the involucre, oblong-ellipsoidal, subcompressed or ovate-cylindrical, slightly 

 pedicelled, either 2-valved from the apex half-way down, or rupturing irregu- 

 larly. Columella linear. Elaters wanting. Spores roundish, smooth. Inflo- 

 rescence monoecious: antheridia immersed in the frond. — Frond orbicular, 

 laciniate, papulose-reticulated, undulate-crisped at the margin, and with dark 

 green oval grains (gemma?) scattered within its substance. (Mem. Amer. 

 Acad. n. ser. 3, p. 64, t. 4. (Name formed of va>ros, the back, and 6v\ds, 

 a purse or bag; from the shape of the involucre and its position on the back of 

 the frond.) 



1. W. valvata, Sulliv. Frond 3" - 8" wide; involucre horizontal-elon- 

 gated, tapering-deflexed ; capsule ovate-cylindrical, horizontal-incurved, 2-valved 

 by a dark-colored suture ; spores light yellowish-brown. (Muse. Alleghan. No. 

 289.) — Moist ground, Central Ohio. (Tab. 20.) 



2. N. melaiiospora, Sulliv. Capsule often without any suture ; colu- 

 mella with short hooked appendages ; spores dark brown, larger than in the 

 preceding, which in other respects it resembles. — Grows in similar localities. 

 (Muse. Alleghan. No. 290.) 



3. flf. orbicularis, Schwein., Sulliv. Involucre nearly erect; capsule 

 oblong-ellipsoidal, subcompressed, the suture evident or obscure : somewhat 

 smaller than the others. — On the ground, North Carolina, Schweinitz: Penn- 

 sylvania, Lesqm eu.r. 



58 



