492 HEPATIC^. 



Hab. — On miicl-covered walls, banks, and rocks. Very rare. 



1. On rocks near Penzance, Cornwall, W. Cnrjww, 1870 

 (Herb. W. H. P.); Trebar- with - Strand, North Cornwall, 

 E. M. Holmes, Mrs. Ma 31. Thulall. 6. Lantyssil, Cardigan- 

 shh-e, W. Joshua, May 1877. 7. On mud-covered walls and 

 banks, Barmouth, Merionethshire,//'^. //. P., April 187G; T.Bogers, 

 Sept. 1877. 



Pound on the Continent and in North America. 



Obs. — A minute but very distinct species, recognised by its 

 two colours, green and purple, and the two rows of cilia. 



Blcc'ia (/laiicescens Carr. is a larger species, more irregular in 

 shape, margin somewhat acute, cilia in a single row. 



Riccia ciliafa Hoffm. is destitute of the purple scales, fronds 

 plane, cilia much more abundant. 



The Biccia fnn/ida, var. Pearsoiil Carr. (Lond. Cat. 12 b. 1881) 

 is a form found in damper situations, where the purple scales are 

 not so evident, fronds thinner, and the cilia not so regularly 

 biseriate ; it approaches B. ciliafa, but from close study of the 

 plant in sifii (Barmouth) I have little doubt but that it is simply 

 R. tiimida modified by its damper habitat. 



Dr. Levier reduces M. tumida to a variety (var. ciliaris) of 

 Kiccia Michelii Paddi, and Herr Stephani refers it to that 

 species ; all the specimens I have seen from different localities, 

 and all I have seen growing for several years at Barmouth, are 

 so regular in size, shape and in having the double row of cilia, 

 that I follow Lindenberg, who described and figured our British 

 form so accurately. 



Descriptiox of Plate CCXXI. — Pig. 1. Plants natural size. 

 2. Frond x ? (Lindenberg). 3-5. Fronds x 24 (Cardiganshire, 

 Wm. Joshua). 6, 7. Cross-sections of fronds x ? (Lindenberg). 

 «, 9. Ditto X 24 (Cardiganshire, Joshua). 10. Ditto x ? (ditto). 

 11-15. Cilia x 64 (ditto). 16. Cilium x 290 (ditto). 



