PLAGIOCHILA. 271 



Greenland, Vahl. 



Obs. — This rare species is not likely to be confused with any 

 other, especially if found fertile. 



Chiloscyphm polyanthos (L.) is a larger plant, with quite 

 different cell structure, and furnished with distinct bipartite 

 stipules. 



I have examined a large series of specimens from different 

 localities, and am of tiie opinion that the var. pyrcnaica is only 

 sportive, as stems which might be described as it are found also 

 on tlie normal form. Dr. Carrington arrived at this conclusion 

 years ago, and Dr. Spruce, who first noticed it, in later years had 

 no great confidence in its specific or varietal value. 



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



2. Portion of stem x 16 (near Bolton Abbey, John Nowell). 



3. Portion of male stem x 16 (Baden, Jack). 4, 5. Leaves x 

 24 (ditto). 6. Portion of leaf x 290 (ditto). 7,8. Stipules x? 

 (ditto). 9-12. Sub-bracts x 11 (ditto). 13. Bracts x 11 

 (ditto). 14. Perianth x 11 (ditto). 15. Cross-section of peri- 

 anth X 11 (ditto). 16. Portion of the mouth of the perianth x 



16 (ditto). IT. Spores x 290 (ditto). 18,19. Perigonial bracts 



X 24 (ditto). 20. Antheridium x 24 (ditto). 



Genus 28. PLAGIOCHILA, Bum. 



Junyermania, Mich. Nov. pi. gen. p. 7 (1729) ; L. Sp. pi. ed. i. 2, p. 1131 (1753) 



CandoUea, Raddi in Act. soc. Modena, 18, p. 22 (1818). 



Martinellia, sect. b. Gr. & B. Nat. Arr. Brit. PI. 1, p. 692 (1821). 



Radula, Dum. Comm. Bot. p. 112, pp. 1822. 



Radula, sect, Plagiochila, Dum, Syll. p. 42 (1831). 



Plagiochila, Dum. Recueil, 1, p. 14 (1835). 



Plants often very large and conspicuous, rarely small, csespi- 

 tose or creeping among mosses. Caudex stout, creeping, densely 

 radiculose on the underside, leafless or furnished with few small 

 ones. Stems firm, reddish, or almost black, rarely pale, 3-5 

 exterior layers of cells coloured, inner pale. Branches ascending 

 or procumbent, dichotomously branched or dendroid, uniformly 

 lateral, springing from the leaf axils. Leaves almost always 



