DESMID FLORA OF DARTMOOR. 



255 



hifunctatum ; C, Corrihense ; C. pseudopyramidatum var. 

 stenonotum ; C. quadrifarium ; G. suhquadrans ; C. tenue ; 

 C. tumidum ; C. venustum ; G. viride. The following desmids, 

 rare in even the richest areas, will be found recorded in the 

 census list given later : Netrium ohlongum var. cylindricum ; 

 Penium exiguum ; Glosterium Ulna ; Euastrum ventricosuum ; 

 E. fulchellum ; E. pinnatum ; Gosmarium connatum ; G. 

 decedens var. ; G. elegantissimum ; G. Nymmanianum ; G. par- 

 vulum ; G. pseudoconnatum ; G. suhundulatum ; Staurastrum 

 aculeatum ; St. furcatum ; St. inconspicuum ; St. lanceolatum ; 

 St. pileolatum. Some twenty species and varieties are now 

 recorded for England for the first time, and about two hundred 

 and fifty are new records for Devonshire. The following table 

 (Table II) shows the various genera represented on Dartmoor, 

 with the number of species, varieties and " forms " in each 

 genus and the percentage of British species (only) in each genus . 



* Fractions of percentages omitted. 



