GYMNOZYGA. 257 



Bambusma Brebissonii var. gracilescens Wolle, Desm. U. S. 1884, p. 25. 

 Gymnozyga nioniUformis var. gracilescens De Toni, Syll. Alsr. 1889, p. 798 ; 



W. & G. 8. West, Some N. Amer. Desm. 1896, p. 232, Cl2, f. 19 ; Alg. 



Ceylon, 1902, p. 194 : Further Contrib. Plankt. Scott. Lochs, 1905, 



p. 506 ; Borge, Sao Paulo Alg. 1918, p. 77, t. 5, f. 38. 



Differs from the typical form only in the smaller 

 relative breadth of the cells. 



Zygospores rectangular with rounded angles. 



Length 24-30 IJL ; breadth 14-17[x ; length of zygo- 

 spore 28-37 IJL ; breadth 18-23[ji. 



SCOTLAND.- -In the plankton ! 



Geoyr. Distribution. Sweden. Ceylon. Java. United 

 States. Brazil. 



VOL. V. 



