COSMARIU3I. 187 



Cosmarium granatum Breb. var. concavum Lagerh. Contrib. aljy. Ecuacl. 



1890, p. 282. 

 Ursinella granata Kuntze, Kevis. gen. plant. 1891, p. 924. 



Cells small, about 1^- times as long as broad, sub- 

 rhomboid-elliptic, deeply constricted, sinus narrowly 

 linear, slightly dilated at the apex ; semicells truncate- 

 pyrainidate, basal angles rounded-subrectangular, sides 

 at the base subparallel, then converging towards the 

 apex, commonly straight or slightly convex (rarely 

 slightly concave), upper angles obtuse, apex narrowly 

 truncate and straight. Side view of semicell elliptic- 

 ovate. Vertical view elliptic, ratio of axes about 

 1 : 1'6. Cell-wall finely punctate. Chloroplasts axile, 

 each with one pyrenoid. 



Zygospore unknown. 



Length 26-47 /x; breadth 19-30 ft; breadth of isth- 

 mus 6-9 /A; thickness 10*5-17'5 //,. 



ENGLAND.- -Cumberland! Westmoreland ! (Bissett). 

 W., X., and E. Yorks ! Lancashire ! Lincolnshire ! 

 Essex! Cambridgeshire! Gloucester ! (Cooke). Sur- 

 rey ! Kent ! Hants ! Devon ! Cornwall ! (Rolfs). 



WALES.- -Capel Curig ! (Cooke ^ Wills), Bethesda !, 

 and Llyn Padarii ! , Carnarvonshire. Dolgelly, Merio- 

 neth (Rolfs). 



SCOTLAND.- -General ! (Roy Bissett). Xot uncom- 

 mon in the plankton ! Orkneys ! Shetlands ! 



IRELAND.- -General ! 



(reof/r. Distribution.- -France. Germany. Austria 

 and Galicia. Poland. Hungary. Italy. Bosnia. 

 Portuo-al. Xorway. Sweden. Denmark. Bornholm. 



O tJ 



Finland. X. and S. Eussia. Siberia. Faeroes. 

 Iceland. Greenland. Spitzbergen. Xova Zembla. 

 Afghanistan. Kordofan. India, Ceylon. Burmah. 

 Central China. Xew Zealand. Australia. AY., Cen- 

 tral, and E. Africa. Madagascar. United States. 

 West Indies. Ecuador (var.). Brazil. Paraguay 

 (var.). Argentina, Patagonia. 



C. granatum Breb. is one of the most widely distributed of 

 all Desmids, being found in every part of the globe which 



