Leucodon.-] A PL O PER I ST OM I, 111 



Gyphomitrion Daviesii. Brid. Meth. p. 31. Schwaegr. Suppl. v. 3. 

 p. 41. t. 113. 



Grimmia Daviesii. 7'wrw. Muse. Hib. p. 24. Hooker and Grevitte, 

 in Edin. Journ. of Science, v. 1. p. 131. 

 Encalypta Daviesii. Enyl. Bot. t. 1281. 

 Griffithia Daviesii. Brown, in Linn. Trans, v. 12. p. 575. 

 HAB. Upon rocks, generally by the sea-shore, on the 

 western coast of England and Wales. Common in 

 similar situations in Ireland, especially on the basaltic 

 columns of the Giant's Causeway. 



Stems rarely exceeding half an inch in height, tutted, bearing 

 a considerable resemblance in habit to Gymnosfomum lapponicum^ 

 and an equally strong one to Trichostomum polypliyllum. 

 Leaves lanceolate-acuminate, carinate, entire, of a dark brown- 

 ish-green colour ; much crisped when dry ; those of the peri- 

 chaetium broad and convolute. Capsule turbinate, beautifully 

 smooth and regular in its form, brown. Lid shortly conical, 

 with a rather long and sharp beak. 



This moss appears to be confined to the British Islands. 



XXI. LEUCODON. 



GEN. CHAR. Fruitstalks lateral; Peristome single, of 32 

 teeth, closely united in pairs ; Calyptra dimidiate. 

 (TAB. II.) 



We have adopted, with much satisfaction, Schwaegrichen's 

 genus Leucodon, published, in the second part of his valuable 

 Supplement to Hedwig's Species Muscorum. The only British 

 species has been severally thrown among the Dicrana, Trichostoma, 

 and Pterogonia ; from any of which an attentive consideration of 

 its lateral fruit, deeply-divided teeth, and dimidiate calyptra, will 

 keep its genus distinct. The teeth are very narrow, whitish, and 

 sometimes appear united at their tops ; but this appearance may 

 arise from our taking as the subjects of our observations capsules 

 in too young a state ; since in specimens which have been gathered 

 fresh from the trees, and in a state where the lid had naturally 



fallen off, the teeth appeared as deeply divided, and the divisions 



10 



