J 10 YORKSHIRE NATURAT,ISTS' UNION. 



52 1. Onychonema Nordstedtianum Turn. 

 N.E — Strensall ! (W. B. Turner). 



S.E. — Riccall Common, abundant. 



Genus SPH/EROZOSMA Corda, 1835. 



522. Sphaerozosma vertebratum (Breb.) Ralfs. 

 S.W. — Rawcliffe Common (W. B. Turner). 



Mid W. — Ingleborough. 



N.E. — Strensall (W. B. Turner). Pilmoor, near Tbirsk, abun- 

 dant. 



S.E. — Riccall Common. 



523. Sphaerozosma excavatum Ralfs. 

 S.W. — In horse-trough, Hainworth, near Keighley. 



INIiD \Y. — Adel Bog (W. B. Turner). Near Selby. Bog two 

 miles south of Clapham. Penyghent. Ribblehead. 

 N.W.— Mickle Fell. 



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

 S.E. — Riccall Common. 



524. Sphaerozosma granulatum Roy & Biss. 

 N.E. — Pilmoor, near Thirsk. 



S.E. — Riccall Common. 



Genus DES.MIDIUM Ag., 1824. 



525. Desmidium cylindricum Grev. 



[Syn. Didyinopriuin Grevillei Kiitz.]. 

 Mid W.— Adel Bog (W. B. Turner). 

 N.E.— Strensall (VV. B. Turner). 



526. Desmidium Swartzii Ag. 



Mid W. — Bramhope (J. Abbott). Ilkley. Cocket Moss, near 

 Giggleswick. 



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



527. Desmidium aptogonum Breb. 



N.E. — Strensall 1 (W. B. Turner). Pilmoor, near Thirsk. 



Var. Ehrenbergii YS\\.^.\^^\^. Aptogonum iiiagonni)i\)^\\^\ 

 N.E. — Strensall Common. 



Var. acutius Nordst. 

 N.E. — Pilmoor, near Thirsk. 



Trails, Y.N.U., iSog (j^ul). .luh' igoi). IJot, .Serits, Vol. 5, 



