72 BRITISH DESMIDIACE.E. 



WALES. Capel Curig and Llyn Padarn, Carnarvon- 

 shire ! Dolgelly, Merioneth ! 



SCOTLAND. Poolewe, Ross ; Presswhin and Bog- 

 wartle in Cromar, and Glen Ey, Aberdeen ; Canlochan, 

 Forfar; Eannoch, Perth (Roy fy Bissett). Craig an 

 Lochan, Perth ! New Galloway, Kirkcudbright ! 



IRELAND. Dublin and TVicklow (Archer). 



Geogr. Distribution. France. Galicia in Austria 

 (var.). Norway. Sweden. Poland. X. Russia. Nova 

 Zembla. Spitzbergen. Greenland. United States. 



The side view of this species easily distinguishes it from 

 any other Euastrum. It seems to be chiefly a northern species. 



44. Euastrum crispulum (Xordst.) nob. 

 (PL XL, figs. 15-18.) 



Euastrum sublobatum Breb. var. crispidum Xordst. Norges Desni. 1873, 



p. 10, t. 1, f . 9 ; De Toni, Syll. Alg. 1889, p. 1042 ; West & G>. S. West, 



Welw. Afric. Freshw. Alg/1897, p. 113. 

 E. pyramidatum West, Alg. W. Ireland, 1892, p. 139, t. 20, f. 13 (figures 



not good) ; Alg. Eng. Lake Distr. 1892, p. 723 ; N-ordst. Index Desm. 



1896, p. 215 ; West & G. S. West, Alg. S. England, 1897, p. 484 ; Some 



Desm. U. S. 1898, p. 287, t. 16, f. 14. 

 ? E. liinale (Turp.) Ehrenb. var. elonyatum Liitkem. Desm. Attersees, 



1892, p. 559, t. 8, f. 11. 



Cells minute, about 1-J- times longer than broad, 

 deeply constricted, sinus narrowly linear with a dilated 

 extremity ; semicells pyramidate-truncate, basal angles 

 rounded, with a slight undulation above the basal 

 angles, upper part of lateral margins retuse ; apex 

 widely truncate, distinctly emarginate in the middle, 

 that part on each side of the apical emargination dis- 

 tinctly retuse, apical angles acutely rounded. Side 

 view of semicell ovate, slightly narrowed near the 

 rounded apex. Vertical view elliptical with a broad 

 inflation at each side. Cell-wall smooth. 



Zygospore unknown. 



Length 25-28 p. ; breadth 16-20 p. ; breadth of 

 apex 9-11 /x; breadth of isthmus 3'5-7'5 /x; thick- 

 ness 12*5-15 p.. 



ENGLAND. Loughrigg, Westmoreland ! Thursley 

 Common, Surrey ! Withiel, Cornwall ! 



