84 BRITISH DESMIDIACE^. 



t}J Semicells globular. 



109. St. subnudibrachiatum* 

 ** Processes in pairs at the angles, all in the same horizontal 



plane. 



110. St. Iceve. 



102. Staurastrum bacillare Breb. 

 (PI. CXLI, figs. 9, 10.) 



Binatella bacillaris Breb. Alg. Falaise, 1835, p. 269. 



Staurastrum bacillare Breb. in Menegh. Synops. Desm. 1840, p. 228 ; RaKs., 



Brit. Desm. 1848, p. 214, t. 35, f. 21 ; Breb. Liste Desm. 1856, p. 145 ; 



Arch, in Pritch. Inf. 1861, p. 741 ; Rabenh. Flor. Europ. Alg. 1868, p. 201 ; 



Wolle, Freshw. Alg. U. S. 1887, p. 41, t, 57, f. 5, 6 ; De Toni, Syll. Alg. 



1889, p. 1186 ; West, Alg. W. Ireland, 1892, p. 173 ; Comere, Desm. de 



France, 1901. p. 173, t. 12, f. 29 ; West & G. S. West, Brit. Freshw. 



Phytoplankton, 1909, p. 202. 



Phycastrum bacillare Kiitz. Spec. Alg. 1849, p. 181. 

 Didymidium (Staurastrum) bacillare Reinsch, Alg. Frank. 1867, p. 153. 



Cells small, deeply constricted, sinus acute and nearly 

 rectangular ; semicells narrowly lunate, angles produced 

 obliquely upwards into thick processes, ending with 

 capitate apices. End view 3-5-angular, sides strongly 

 concave, angles produced with capitate apices. Cell- 

 wall smooth. 



Zygospore unknown. 



Length, without processes, about 16'2(ji ; with pro- 

 cesses, 33 '8 ^; breadth, with processes, 30-37 '5^; 

 breadth of isthmus 7-87 p. 



IRELAND.- -Lough Aunierin, Co. Gal way ! Minister 

 and Connaught (Adams). 



Geogr. Distribution.- -France. Germany. Poland. 

 Burma. United States. West Indies. 



Var. obesum Lund. (PL CXLI, figs. 11, 12.) 



St. bacillare var. obesum Lund. Desm. Suec. p. 57, t. 3, f. 24 ; De Toni, Syll. 

 Alg. 1889, p. 1187 ; West, Alg. N. Wales, 1890, p. 16, t. 5, f. 4 ; Alg. W. 

 Ireland, 1892, p. 173 ; Eichler, Mat. nor. Miedz. 1894, p. 133, t. 4, f. 55. 



A variety with proportionately larger body of semi- 

 cell ; processes horizontal and very much reduced, 

 almost entirely wanting, apex of cell slightly convex. 



