HANDBOOK OK IJRI'l ISH HEPATICit. 1 55 



Genus 23. PLAGIOCHILA, Dumort. 



Involucre diphyllous, somewhat conform- 

 ing to the leaves, but larger ; leaves simple, 

 flattened ; perianth compressed at the sides, 

 flattened, mouth oblique, truncate, dentate, 

 or ciliate, somewhat lipped, hence split ; cap- 

 sule four-valved, coriaceous, decussate, naked; 

 elaters geminate, naked, deciduous. — Dimiort. 

 Hep. t. I,/ II. 



Leaves dimidiate, not conduplicatc, nor auricu- 

 late, without a dorsal lobule. 



Fructification terminal, or from the growth of 

 innovations axillary. Autoicous or dioicous. 

 Perianth laterally compressed, erect, or decurved 

 at the apex; mouth obliquely truncate, bilabiate, 

 entire, or ciliate. . Involucral bracts two, erect. 

 Pistillidia numerous. Capsule thick, four-valved. 

 Elaters bispiral. Andraecium spiral. Perigonial 

 leaves smaller, closely imbricate in two rows. 

 Primary shoots leafless, creeping, with rootlets. 

 Leaves succubous, distichous, or subsecund, dorsal 

 margin decurrent, entire, ventral arcuate, entire, or 

 cut. Amphigastria inconspicuous. — Carr. Br. 

 Hep. 51. 



Plagiochila asplenioides, Vaill., Dum. 



Stem ascending, branched ; vertical leaves 

 subcurrent, rounded-ovate, convex, slightly 

 recurved, dentate ; perichaetial leaves revolute 



