CLOSTERIUM. 371 



This species comes near to Closterium DiancB Ehr., which, 

 however, is a more elongated and more slender plant. 



3. Closterium Dian^ Ehr, 



Plate LXXXIV. Fig. 5. 



Char. Frond slender, much attenuated towards each end. 

 Granules in a single series down the centre. Endochrome 

 fasciated. Fasciae obscure. 



CI. riificeps, Abhandl. der Akademie d. Wissench. zu Ber- 

 lin, 1831, p. 67. CI. DiancE Ehr., Die Infus. p. 92. t. v. 

 f. 17. 



Hah. Chiltington Common, near Pulborough : Mr. Jenner. 

 A distinct and elegant species. 



b. Closteria curved, not appendaged, striated. 



4. Closterium turgidum Ehr. 



Plate LXXXYII. Fig. 3. 



Char. Frond large, slightly curved, suhcylindrical, but little 

 attenuated, very -finely striated. Apices roundish and 

 rubescent. 



Closterium turgidum Ehr., Infus. tafel vi. fig. 7. ; Jenner, 

 in Flora of Tunbridge Wells, p. 196. 



Hab. Several places in Sussex : Mr. Jenner. 



The stride in this species are finer, and the frond larger 

 than in Closterium striolatum. 



5. Closterium striolatum Ehr. 



Plate LXXXVII. Fig. 4. 



Char. Frond fusiform, gradually attenuated towards each 

 end, evidently striated, ten or tv-elve times as long as broad. 

 Extremities rounded. 



B B 2 



