KCASTKOJ. 73 



SCOTLAND. Rhiconich, Sutherland ! Lewis, Outer 

 Hebrides ! 



IRELAND . Ballynahinch, Kylemore, and Eoundstone, 

 Gal way ! 



Geogr. Distribution. Norway. W. Africa. United 

 States. 



The Desmid we described from Ireland as Euastrum 

 pyramidatum is identical in every respect with that described 

 by Nordstedt from Norway as Euastrum sublobatum var. 

 crispulum. It is a very constant species, easily distinguished 

 from E. sublobatum, and we have therefore placed it as 

 Euastrum crispulum . 



It is smaller than E. sublobatum, the semicells are pyra- 

 midate (not quadrate), and the undulations above the basal 

 angles and the undulated character of the apex are features 

 which are never present in E. sublobatum. In the vertical 

 and side views the central inflation of E. crispulum appears 

 very much smaller than that of E. sublobatum. 



45. Euastrum sublobatum Breb. 

 (PL XL, fig. 19.) 



Euastrum sublobatum Breb. in Ealfs' Brit. Desm. 1848., p. 91, t. 32,, f . 4 ; 



Nordst. Index Desru. 1896, p. 245. 

 Cosmarium sublobatum (Breb.) Arch, in Pritch. Infns. 1861, p. 731 ; 



Kabenh. Flor. Europ. Algar. Ill, 1868, p. 168; Kirchn. Alg. Scliles. 



1878, p. 152 ; Wolle Desm. U.S. 1884, p. 80, t. 18, f. 21, 23 ; Cooke, Brit. 



Desrn. 1886, p. 79, t. 36, f . 1 ; De Toni, Syll. Alg. 1889, p. 1041 ; West. 



Alg. Eng. Lake Distr. 1892, p. 723 ; West and G. S. West, Alga-fl. 



Yorks. 1900, p. 90; Alg. X. Ireland, 1902, p. 32. 

 r.-sinella sublobata Kimtze, Eevis. gen. plant. 1891, p. 925. 



Cells small, about 1-J- times as long as broad, deeply 

 constricted, sinus narrowly linear with a widely-dilated 

 extremity ; semicells snbquadrate, lateral margins 

 retuse, basal angles rounded, superior angles more 

 acutely rounded, apex convex-truncate, retuse-emar- 

 D-inate in the middle. Side view of semicell ovate, 



o 



with a large protuberance on each side near the base, 

 upper part of lateral margins retuse, apex rounded; 

 vertical view elliptic, with a large protuberance in the 

 middle on each side, giving it a subcruciform appear- 

 ance. Cell- wall smooth. 

 Zygospore unknown. 



