68 YORKSHIRE NATURALISTS' UNION. 



289. Xanthidium fasciculatum Ehrenb. 



N.E. — Strensall (\V. B. Turner). Pilmoor, near Thirsk. 



290. Xanthidium Brebissonii Ralfs. 



Mid W. — Bog two miles south of Clapham (iv. 1898), 

 N.E. — Strensall (W. B. Turner), a variety. 



291. Xanthidium aculeatum Ehrenb. 



Mm W. — Ilkley (W. H. Dikes). Cocket Moss, near Giggles- 

 wick. 



N.W.— Cronkley Fell. 



N.E. — Strensall ! (W. B. Turner). Pilmoor, near Thirsk. 



S.E. — Riccall Common. 



292. Xanthidium variabile West & G. S.West in Journ. 



Bot., Aug. 1900, p. 291. [Syn. X.Smithii Arch. var. 

 variabile Nordst. 1887]. 



N.W.— Mickle Fell. 



We have found this plant in many parts of England, and from 

 some localities (especially certain Sphagjiufu-hogs) it is very 

 abundant. It retains its distinctive characters in such a con- 

 stant manner that we feel compelled to regard it as a distinct 

 species from X. Smithii. Moreover, we never find X. variabile 

 associated with X. Smithii; and although the former varies 

 considerably, yet no forms are met with intermediate between 

 the two species. (Cfr. G. S. West in Journ. Linn. Soc, Bot. vol. 

 xxvii., 1899, p. 386, t. 8, f. 20 — 22). 



293. Xanthidium concinnum Arch. 1883. 



[Syn. Arthrodesmus hexagon us Boldt, 1885]. 

 Mid W. — Bog two miles south of Clapham. 



Genus COSMARIUM Corda, 1834. 



294. Cosmarium Ralfsii Br(^b. 

 Mid W.— Cam Fell (viii. 1896). 



N.W.— Mickle Fell. Lund's Fell (iv. 1898). Mossdale Moor, 

 Widdale Fell. Bog near Widdale Beck. 



295. Cosmarium circulare Reinsch. 

 N.W.— Mickle Fell. 



Trans. Y.N.U., 1897 (pub. Dec. 1900). Bot. Series, Vol. 5, 



