90 HEPATICJE. 



cells -02 mm. x '025 mm., '025 mm. x '025 mm., -03 mm. x 

 •02 mm., '04 mm. x "02 mm. ; stipules '8 mm. x '6 mm., '4 mm. x 

 •15 mm., -4 mm. x '25 mm., *35 mm. x '25 mm., 7 mm. x '4 mm. ; 

 perianth 2' mm. x 1'25 mm. 



Hab. — On damp shaded rocks or stones, very rare. 



1. Eiver side, Fingal Bridge, Devonshire, JF. Curnow. 



1. South of Ireland, Br. Taylor, Br. Moore, A. Carroll, &c. 

 Lough Mangerton, Stewart and Holt. 



Found sparingl}^ on the Continent (France), also in North 

 America. 



Obs. — This is the smallest and most delicate of the British 

 Porellcs, and is nearest related to P. rivularis, which see. 



The description of the fertile plant is taken from North 

 American specimens by Dr. Gottsche, sterile plants only having 

 been found in Europe. 



Description of Plate XXXII.^ — Fig. 1. Plant natural size, 



2. Portion of stem, antical view x 16 (C. and P. n. 132). 3. Ditto, 

 postical view x 11 (ditto). 4, 5. Lobules x 24 (Mangerton, Holt 

 and Stewart). 6. Portion of stem, witli lobules and stipules x 31 

 (C. and P. n. 132). 7. Lobule x 64 (ditto). 8. Portion of leaf 

 X 290. 9, 10. Stipules X 24 (Mangerton, Holt and Stewart). 

 11. Stipule X 31 (ditto). 12. Ditto x 64 (C. and P. n. 132). 



Genus 6. PLEUROZIA, Bum. 



Jungermania, Weiss, PI. Crypt. Fl. Gott. p. 123 (1770). 



Pleurozia, Dum. Recueil, i. p. 15 (1835). 



Physiotiuin, Nees, Nat. Eur. Leb. 3, pp. 6 and 75 (1838). 



Involucral bracts two, deeply bilobed, the upper broad and 

 convolute. Perianth much exserted, long, cylindrical, mouth 

 denticulate, decurved and plicate at the apex. Capsule 4-valved, 

 coriaceous. Elaters bispiral, deciduous. Stipules absent. Leaves 

 with postical lobes auriculate, the auricles inflated. 



