34 BEITISH DESMIDIACEJS. 



SCOTLAND. Locli Inver, Sutherland!; Poolewe, Ross; 

 South Birsemore, Aberdeen ; Grlen Clova, Forfar ; 

 Arnbathie Loch, Perth ; Glen Coe, Argyll (Roy & 

 Bissetf). Rhiconieh, Sutherland ! 



Geogr. Distribution. Norway. Sweden. Poland. 

 Greenland. Ceylon (var.). Azores. United States. 



19. Euastrum Webbianum Turn. 

 (PI. XXXVII, fig. 7.) 



Euastrum Welbianum Turn. Freshw. Alg. E. India, 1893, p. 86 (formee 

 major et minor}, t. 22, f . 4 ; Turn. Desmid Notes, 1893, p. 343, f . 4 

 (forma major). 



Cells rather small, about twice as long as broad, 

 deeply constricted, sinus widely open but narrowed 

 towards the extremity ; semicells subpyramidate, with 

 concave sides, and projecting, subconical (slightly up- 

 turned) basal angles, apex truncate with a narrow 

 median incision. Cell- wall smooth. 



Forma minor: length 26-30^; breadth 13- 16 ft; 

 breadth of isthmus 4 p. 



Forma major : length 58 //, ; breadth 28 //, ; breadth 

 of isthmus 8 //,. 



ENGLAND. Sutton Park, Warwick (forma major, 

 Turner). 



Geogr. Distribution. X. India (forma minor). 



This small "Euastrum," which has been but imperfectly 

 described by Turner, appears to us as very probably two 

 dislocated cells (each in an oblique position) from a filament 

 of Desmidium Swartzii or some allied species. 



20. Euastrum Sendtnerianum Reinsch. 

 (PL XXXVII, fig. 8.) 



Euastrum Sendtnerianum Eeinsch, Spec. Gen. Alg. 1867, p. 119, t. 21, 



f. C. II 1-6 ; De Toni, Syll. Algar. 1889, p. 1079. 

 Didymidium (Euastrum) Sendtnerianum Eeinsch, Algenfl. Frank. 1867, 



p. 135, t. 9, f . 4. 

 Cosmarium (Euastrum} Sendtnerianum Wolle in Bull. Torr. Bot. Club. 



1885, p. 3, t. 47, f. 30-31 ; Wolle, Freshw. Alg. U.S. 1887, p. 29, t, 57, 



f. 30, 31 ; Gutw. Flor. Glon. Okolic Lwowa, 1891, p. 40. 

 Helierella Sendtneriana Kuntze, Revis. gen. plant. 1891, p. 899. 



