265 



NEW VARIETIES OF BRITISH MOSSES. 



Br D. A. Jones. 



(Plate 549.) 



Camptlopus setifolius Wils. var. i^TERMEDrus, var. nov. 



In November 1900 I gathered a Campylopiis by the side of a 

 stream m Cwm Mawr, Harlech, which, while possessing some of the 

 characteristics of C. jiexuosus Brid., showed also some resemblance to 

 C. setifolius Wils. After further examination it was sent to the 

 Moss Exchange Club as an unnamed variety of C jiexuosus. Mr. R. 

 H. Meldrum, the referee, agreed that it belonged to that species, and 

 that it did not tit with the descriptions of any of the named varieties, 

 but considered that it was inadvisable in so variable a species to add 

 to the number of named forms. In March last I visited the same 

 district and found the plant under better conditions and in greater 

 quantities on the stony ground along the shore of Llyn Eiddew Mawr. 

 It distinctly resembles C. setifolius, which occurs in the same Cwm, 

 as it has the glossy appearance and slender habit with long, setaceous, 

 rigid, denticulate leaves so characteristic of that species. The upper 

 leaves, however, are slightly flexuose. The nerve is generally broader 

 than in C.fiexuosus, although in some of the lower leaves it is quite 

 as narrow. In section, also, the anterior cells are much larger than 

 the Deuter and therefore much more like those of C setifolius^ as men- 

 tioned by Mr. H. N. Dixon. The basal cells are laxer and with thinner 

 walls than is usually found in either of the two species. The auricles 

 are inflated and hyaline, showing a tendency to be coloured in the 

 inner part towards the base of the nerve. I regard this plant as 

 intermediate between C. setifolius and C. flexuosus with a nearer 

 approach to the former. 



A beautiful form approaching this variety occurs on damp rocks 

 in Cwm Bychan, Harlech, where I gathered it in the company of 

 Mr. E. Cleminshaw in April 1915. The stems are tall with glossy, 

 falcate leaves. The upper leaves are distinctly flexuose and in nerve 

 section and basal areolation are nearer C. flexuosus ; the leaves, 

 however, are more denticulate than is usual in that variable species. 

 A similar form has been found by Mr. J. Hunter at South Barrule, 

 Isle of Man. I would label these two plants, C. flexuosus Brid., 

 approaching C. setifolius var. intermedius : — 



Campylopus setifolius Wils. var. intermedius mihi. 



Csespites alti, lati, extensi, nitide satui-ato-virescentes ; plantulse 

 paullo minus graciles, infra exigue radiculosae ; folia minime conferta, 

 erecto-patentia, recta, madore rigida siccitate flexuosa, basi nitenti, 

 superiora baud tam longe setacea ; margo pro maxima parte tubularis, 

 parte superiori, sed non tam longe ab apice, denticulatus, vix tamen 

 serratus ; costa lata, dorso superius vix spinuloso-denticulato ; cellulis 

 ventralibus quam eurycystis in sectione transversali multo majoribus ; 

 auriculae grandes vitreae parte interiore nonnunquam coloratse ; cel- 

 lulse basilares laxiores, minus distinctae, parietibus tenuioribus. 



Hah. — In locis humidis saxosis prope lacum Eiddew Mawr ; 

 prope Cwm Bychan ; in comitatu Merioneth. 



Journal of Botany. — Vol. 55. [Octobek, 1917.] v 



