213 



posed in 4 curved transverse series, 4 in each upper 

 and lower series, and o in the median series). Side 

 view of semicell obovate-circular, with 4 prominent 

 grannies on each lateral margin. Vertical view elliptic, 

 with o laro-e granules at the middle on each side, 



o o 



polar regions granulate, but destitute of granules in 

 the centre. 



Zygospore unknown. 



Length 28-30 p; breadth 25-27 p.; breadth of 

 isthmus 5'3 /LI (9*5 /x according to Xordstedt) ; thick- 

 ness 18 ju. 



ENGLAND.- -Gormire, X. Yorks. (IF. B. TUI'IKT). 



SCOTLAND.- -Pool near Craithes Station, Kincardine 

 (Roy $ Bis sett). 



Geofjr. Distribution.- -NoTW&y. Sweden. Sandwich 

 Islands. United States. 



C. anisochondrum is closely allied to C. punciulatum var. 



subpunctulatum,\)\\i differs in its mucli deeper constriction, in 

 the rectangular basal angles of the semicells, and in the 

 acuteness of tlie general grannies. The central grannies are 

 also of a different character, and occupy a greater longi- 

 tudinal extent (from apex to isthmus) than do those of any 

 known form of C. punctulatum var. subpunctulatum. 



The Desmid recorded and figured by Borge (' Beitrage Alg. 

 Schweden/ 1906, p. 32, t. 2, f. 17) under the name of " C. aniso- 

 chondrum forma ;I is typical C. Boeckii Wille, both as regards 

 its granulation and dimensions. 



190. Cosmarium bipunctatum Borg. 

 (PL LXXXV, fig. G.) 



Cosmarium bipunctatum Borg. Desm. Brasil. 1890, p. 40, t. 4, f. 33; West, 

 Alg-. W. Ireland, 1892, p. 153 ; Norclst. Index Desm. 1896, p. 62. 



Cells small, almost as long as broad, deeply con- 

 stricted, sinus narrowly linear w^ith a very slightly 

 dilated extremity ; semicells widely trapeziform, basal 

 and apical angles obtuse, sides convex, apex widely 

 truncate, margins undulate-crenate (with G crenations 

 at the apex and G along each side), with two irregular 

 series of small granules within the margin, and with 



