ami A. 409 



instaaces descending to sea-level, Dr. D. Moore. On rocks near 

 the tunnel, Cromaglovvn, Dr. Carriiujlon ; Dankerron and Knock- 

 avoila, Dr.Tai/lor ; Carnintual, Dr. J). Moore; Lugnaquilla, Co. 

 Wicklow, and Graltymore, A. Carroll ; rocks on the Hill of Howth, 

 Br. B. Moore ; Golden Kiver, Co. Louth, llev. 11. W. Lett. 



Found on the Continent (Norway). 



Obs. — This is a very distinct species and abundantly different 

 from any other of the genus, Cesia ohtma, Lindb., is far removed 

 from it by its larger size, different colour and shape of leaves, the 

 marginal cells of which are rounder and smaller. 



Dr. Carrington was the first to distinguish this species, which 

 had been referred by Dr. Taylor to Cesia coraUioideH (Nees). He 

 sent specimens as a new species to Dr. Grottsche, who gave it the 

 characteristic name of crenidata. 



Although generally distributed in the mountainous parts of 

 the British Isles, it appears to be very rare on the Continent, and 

 not well understood by some authorities, Herr Limpricht, a most 

 acute hepaticologist, and whose devotion to the European mosses 

 has evidently interfered of later years with his study of the 

 Hepaticae refers Cesia oblitsa to C. crenulala, as a variety of 

 C. concuuiaia (lA^\\it),[G^uiiioniitriuiu eonclnnat((ui,Ni\M. crenulattim), 

 (Cohn's Krypt. Schles. 1, p. 24G (1877) ). 



It generally grows at a lower elevation than any other species 

 of the genus. Mr. Macvicar has found it at sea-level in Scotland, 

 and it is one of the commonest species on rocks and walls about 

 Llanberis in North Wales, and Seathwaite in Borrowdale. 



Description of Plate CLXXX. — Fig. 1. Plants natural size. 

 2. Branch x 20 (Dr. C). 3. Fertile branch x 40 (ditto). 4. 

 Apex of barren branch x GO (ditto). 5. Portion of stem x 24 

 (Pass of Llanberis, W. H. P.). G. Leaf x 85 (ditto). 7. Ditto 

 (Cader Idris, W. H. P.) 8. Leaves x (Dr. C). 1). Portion of 

 the apex of a leaf, showing the crenate margin x oOO (Dr. C). 

 10. Portion of leaf x 290 (Long Stile, G. Stabler). 1 1. Marginal 

 cells X 290 (ditto). 12, 13. Bracts x 85 (Pass of Llanberis, 

 W. H. P.). 14. Bract enclosing the calyptra and capsule x 

 (Dr. C). 15. Pistillidia surrounded by the innermost bracts x 



