84 BRITISH DESMIDIACE.E. 



SCOTLAND. Sutherland ! , Ross, Inverness ! , Aber- 

 deen, Kincardine, Forfar, Perth ! , Stirling, Arran 

 ( llnij ^ 7//.s-.sv/f). Kirkcudbright ! Harris, Outer Hebri- 

 des ! Shetlands ! 



IRELAND. Kylemore, Roundstone and Ballynahinch, 

 Galway ! Castletown and Carrantuohill, Kerry ! 

 Dublin and Wicklow (Archer}. Slieve Donard, Down ! 



Genyr. Distribution. France. Germany. Austria. 

 Poland. Hungary. Italy. Portugal. Norway. 

 Sweden. Finland. Lapland in Russia. Faeroes. 

 Greenland. Spitzbergen. Java. New Zealand. East 

 Africa. Azores. United States. Ecuador. 



There is frequently a terminal vacuole at each extremity of 

 the cell, containing moving granules. 



11. Penium Cylindrus (Ehrenb.) Breb. 

 (PI. VI, %s. 1-3.) 



Closterium ? (Toxotium) Cylindrus Ehrenb. Infus. 1838, p. 95, t. 6, f. vi ; 



Menegh. Synops. Desm., 1840, p. 236. 

 Penium Cylindrus (Ehrenb.) Breb. in Ralfs' Brit. Desm. 1848, p. 150, t. 25, 



f. 2 ; Arch, in Pi-itch. Infus. 18(51, p. 750; Rabenh. Flor. Europ. 



Algar. Ill, 1868, p. 122 ; Cooke, Brit. Desm. 1886, p. 39, t. 17, f. 2 ; 



West, Alg. W. Ireland, 1892, p. 126 ; Alg. Eng. Lake Distr. 1892, p. 



720 ; Roy and Biss. Scott. Desm. 1894, p. 251 ; Nordst. Index Desm. 



IS! 1(3, p. 96 ; West & G. S. West, Alg. S. England, 1897, p. 478 ; Alga-fl. 



Yorks, 1900, p. 44 ; Alg. N. Ireland, 1902, p. 21. 

 Dysphinctium Cylindrus Nag. Gatt. einz. Alg. 1849, p. Ill ; Hansg. Prodi- . 



Algenfl. Bolira. 1888, p. 186. 



Cylindrocystis Cylindrus Reinsch, Algonfl. Frank. 1867, p. 198. 

 Calocylindrus Cylindrus a. genuinus Kirchn. Alg. Schles. 1878, p. 142. 

 Calocylindrus Cylindrus b. silesiacus Kirchn. I. c. 



Cells small, 2-4 (rarely up to 0) times longer than 

 their diameter, cylindrical and unconstricted, apices 

 truncately rounded ; cell-wall reddish-brown in colour 

 and furnished with longitudinal rows of minute 

 granules, which are often scattered, especially near the 

 extremities. 



Zygospore globose and smooth. 



Length 30-50 /u ; breadth 10-5-14 //; diam. zygosp. 

 25-27^. 



ENGLAND. Cumberland ! Westmoreland ! (/M///N). 

 \V. and N. Yorks ! Lancashire! Warwick (Wills). 

 Surrey (with zygospores, from Thursley Common) ! 



