HErATICjE. (liverworts.) G89 



Suborder IV. JENGERMAWNIACEJE. Scale-Mosses. 



Either frondose or foliaceous : leaves when distinct 2-ranked, and often 

 with a third row of smaller ones (amphigastria) on the under side of the 

 stem. Capsule on a cellular pedicel, dehiscent lengthwise into 4 valves. 



I. Vegetation frondose (stem and leaves confluent in a frond). 



13. METZGERIA, Raddi. (Tab. 21.) 



Fertile fructification arising from the lower surface of the midrib of the frond. 

 Involucre 1-leaved, scale-like, at length ventricose and 2-lobed. Perianth none. 

 Calyptra ascending, oblong-obovate, rather fleshy. Capsule ovate. Elaters 

 with one spiral fibre, adherent to the tip of the valves. Inflorescence dioecious : 

 antheridia 1-3, enclosed by a 1-leaved involucre on the under side of the mid- 

 rib. Ovate gemmae aggregated on the attenuated tips of the linear frond : mid- 

 rib distinct. (Named for J. Metzger, a German botanist.) 



1. M. furCiita, Nees. Fronds linear, thin and membranaceous, forking 

 or proliferous, with white pellucid hairs on the margins, and beneath on the 

 midrib ; calyptra hispid. — Hilly districts, on rocks and the bark of trees. (Tab. 

 21.) (Eu.) 



2. M. pmtoesceus, Raddi. Larger than the last, pubescent on both 

 surfaces. — Mountainous localities. (Eu.) 



1.4. AN EUR A, Dumortier. (Tab. 21.) 



Fructification arising from the under side near the margin of the frond. In- 

 volucre cup-shaped, very short and lacerate, or none. Perianth none. Calyp- 

 tra ascending, nearly cylindrical, fleshy. Capsule oval or oblong. Elaters 

 adherent to the apex of the valves, containing a single broad spiral fibre. Inflo- 

 rescence dioecious. Antheridia immersed in the upper surface of receptacles 

 proceeding from the margin of the frond ; which is fleshy and destitute of a 

 midrib (whence the name, from a privative, and vevpov, a nerve). 



1. A. SeSSiliS, Sprengel? Fronds irregularly lobed (l'-2' long, 3" -5" 

 wide); involucre none ; calyptra papillose at the apex; pedicel 9"- 12" long, 

 sometimes folded upon itself and remaining within the calyptra, thus making 

 the capsule appear sessile ; sterile receptacles elongated, and tapering deflexed 

 processes. (Mem. Amer. Acad. n. ser. 3, p. 62, t. 5.) — Rotten logs, margins of 

 swamps, Ohio ; rare as high as lat. 40 ; very common in the Southern States. — ■ 

 This may not be Sprengel's plant, the leaves of which are described as having 

 large oblong areola?, and the calyptra as being smooth. (Tab. 21.) 



2. A. piElguis, Dumort. Much like the last; frond more linear and 

 simple ; involucre short and lacerate ; sterile receptacles 2-lobed, lobes obtuse. 

 — Among Sphagnum, in the Southern States (Schweinitz) ; and in Ohio. Fruit 

 not seen. (Eu.) 



3. A.. jmlBmatil, Nees. Fronds usually crowded (2" -3" high), ascend- 

 ing, palmately divided, the divisions linear and obtuse ; sometimes prostrate and 

 creeping extensively; calyptra tuberculate. — Rotten logs, &c. ; common. (Eu.) 



58* 



