ENCYONEMA. 439 



2. SURIRELLA JENNERI Hass. 

 Plate CII. Fig. 15. 



Char. Frustules in front view obtuse at each extremity, and 

 with stria in double series ; end view quadrangular, each 

 angle being prolonged into a thin plate. 

 Surirella bifrons Jenner, loc. cit. p. 204. 

 Hob. Warbleton : Mr. Jenner. 



A very distinct and beautiful production, having no re- 

 lation with the N. bifrons of Ehrenberg. 



/ 



87. ENCYONEMA Kiltz. 



Char. Frustules cymbiform, enclosed within a membrane. 

 Derivation. From sy/cvos, full, and vrj/Aa, a thread. 



1. ENCYONEMA PROSTRATUM Kutz. 



Plate C. Fig. 10. 



Char. Frustules striated, straight, gibbous, small, enclosed 

 within a transparent membranous tube. 



Encyonema prostratum Kutz., Die Kreselschaligen, &c. 

 p. 82. t. 25. f. 7. Encyonema paradoxum Kutz., Synops. 

 Diatom. Monema prostratum Berk., Glean, of Br. 

 Algae. Schizonema 9 prostratum Grev., in Hook. Br. FL, 

 p. 414. ; Harv. in Manual, p. 214. Encyonema pros- 

 tratum Jenner, in Fl. of Tunbridge Wells, p. 206. 



Hab. On the boards of a sluice forming a thin, brown 

 mucous stratum : Rev. J. M. Berkeley. On the boards 

 of a sluice on Cheshunt Marshes : A. H. H. Bramble- 

 tye, near Forest Row, and in the stream which parts 

 Sussex and Kent, between Bodiam and Sandhurst. 



A very singular and beautiful production, coming near to 

 Schizonema. 



