151 



Cells large, stout, 6-7 times longer than their dia- 

 meter, almost straight, outer margin 4045 of arc, 

 inner margin generally straight and very slightly tumid 

 in the median part, gradually and gently narrowed to 

 the apices, which are slightly recurved and obtusely 

 rounded; cell- wall smooth and colourless ; chloroplasts 

 with about ten to twelve ridges and numerous scattered 

 pyrenoids; terminal vacuoles with a large cluster of 

 moving granules. 



Zygospore globose and smooth. 



Length 478-680 /A; breadth 76- 11 6 /x ; breadth of 

 apices about 19-23 p. 



ENGLAND. Cumberland! Westmoreland! W., N., 

 and E. Yorks ! Lancashire! Cheshire (Ifulfs). 

 Leicester (li<nj). Norfolk (CWv). Warwick (Wills). 

 Surrey! (Ba'lfs). Sussex (R,tlfs). Kent! (Rolfs). 

 Hants! (Bennett). Devon! Cornwall ! (Ralfs). 



WALES. General ! 



SCOTLAND. General ! (lfi.ii/ mid Bissett). General in 

 Outer Hebrides ! Orkneys ! 



IRELAND. - - Donegal ! Mayo ! Galway ! Kerry ! 

 Dublin and Wicklow (Archer). Down ! 



(ii'oqr. Distribution. France. Germany. Switzer- 

 land. Austria and Galicia. Hungary. Italy. Portu- 

 gal. Norway. Sweden. Denmark. Bornholm. N. 

 and S. Russia. Caucasus. Faeroes. Iceland. Nova 

 Zembla. Japan. India. Australia. New Zealand. W. 

 and E. Africa. United States. Mexico. W. Indies. 

 Brazil (var.). Ecuador. Paraguay. Uruguay. Patagonia, 



This characteristic Desinid is not found in the situations in 

 which Cl. acrroxnnt, Cl. lanceolatum, and Cl. Ehrenbergii are 

 nl'U'ii abundant. It lias a decided preference for bogs and is 

 commonly found in association with Eremosphaera viridis. 



Forma minor 



Cl. Lunula forma, G. S. West, Alga-fl. Cambr. 1899, p. 111. 



Smaller than the typical form, with a faintly straw- 

 coloured cell-wall. 



