52 BRITISH DESMIDIACEJ-:. 



77. Cosmarium Norimbergense Reinsch. 

 (PI. LXIX, figs. 25-27.) 



Cosmarium Norimbergense Reinsch, Spec. Gen. Alg. 1867, p. 117, t. 22 A iv, 



f. 1-11 ; Lund. Desm. Suec. 1871, p. 43 ; De Toni, Syll. Alg. 1889, 



p. 960; Eoy & Biss. Scott. Desm. 1894, p. 169; Nordst. Index Desm. 



1896, p. 183 ; West & G. S. West, Freshw. Alg. Ceylon, 1902, p. 166. 

 C. Hammeri Reinsch f. D. octogibbosum Eeinsch, Spec. Gen. Alg. 1867, 



p. 115, t. 22 B i, f. 13-19. 

 Didymidium (Cosmarium} Norimbergense Eeinsch, Algenfl. Frank. 1867, 



p. 113, t. 9, f. 2. 

 Cosmarium octogibbosum Eeiiisch, Alg. Prom. Bon. Spei, 1877, p. 240 ; 



Turn. Freshw. Alg. E. India, 1893, p. 52. 

 C. Meneghinii Breb. var. Wollei Lagerh. Desm. ans Bengal, 1888, p. 8 



[C. Meneghinii Wolle, Desm. U. S. 1884, t. 16, f. 7 sinistra superior] ; 



West, Alg. W. Ireland, 1892, p. 149, t. 24, f. 18 [forma monstrosa] ; 



West & G. S. West, Alg. S. England, 1897, p. 487; Alga-fl. Yorks. 



1900, p. 93. 



Ursinella Norimbergensis Kuntze, Eev. gen. plant. 1891, p. 925. 

 Cosmarium octogibbosum Eeinsch var. indica Turn. Freslnv. Alg. E. India, 



1893, p. 52, t, 8, f . 8. 



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

 constricted, sinus narrow with a dilated apex ; semi- 

 cells subquadrate, sides retuse, upper and lower angles 

 rounded, apex retuse, almost straight, or very slightly 

 convex. Side view of semicell oblong-elliptic. Verti- 

 cal view elliptic, ratio of axes 1 : 1*6. Cell-wall smooth. 

 Chloroplast axile with a single central pyrenoid. 



Zy go spore unknown. 



Length 12-23 /i; breadth 8-13'3/x,; breadth of 

 isthmus 3-5 '5 ^ ; thickness 6*7-9 p. 



ENGLAND.- -Biccall Common, E. Yorks ! Dartmoor, 

 Devonshire ! 



WALES.- -Yr Orsedd, Carnarvonshire ! 



SCOTLAND.- -Slewdruni, Aberdeen; marsh X. AY. 

 f rom Menmuir Church, Forfar (Roij Bissett). 



IRELAND.- -Roundstone, Gralway ! Cromagloun, Upper 

 Lake of Killarney, and Carrantuohill, Kerry ! 



Geoc/r. Distribution. --Germany. Hungary. Swe- 

 den. Bornholm. Finland. India (var.). Ceylon, 

 Siam. New Zealand. Central Africa. 



This small species is nearly related to C. obliquum Nordst., 

 and perhaps to C. exiguum Arch. 



