ZYGNEMA. 159 



rangia oval, lodged in cells, which are considerably in- 

 flated. 



Hab. In a wet spot by the road side between Dudsland 

 toll-gate and the Hall Farm, Mayfield ; in the pond at 

 Ramslye; in the watercourse by the road side near 

 Mark Cross, &c. : Mr. Jenner. Cheshunt : A. H. H. 



To this species, which is certainly a distinct one, I have 

 assigned the name of Mr. Jenner, whose zeal and acuteness 

 in the cultivation of a knowledge of the freshwater Algae, as 

 well as in the pursuit of other departments of Natural History, 

 are so eminent. I could have wished that it had been more 

 worthy to have borne his name ; it has one advantage, how- 

 ever, over some others, which is this, that it is an abundant 

 species. 



41. ZYGNEMA DUBIUM Hass. 

 Plate XXXVII. Fig. 7. 



Char. Filaments rather more slender than those of Z. Jen- 

 neri. Cells flve or six times as long as broad. Sporangia 

 oval, long, placed in cells, which are inflated for their 

 reception. 



Hab. Between Sidley Green and Ninfield, near Battle : 

 Mr. Jenner. Near Wormly West End, Hertfordshire : 

 A. H. H. 



This may be but a variety of Zygnema Jenneri. 



42. ZYGNEMA MINIMUM Hass. 

 Plate XXXVII. Fig. 8. 



r. Filaments as slender as those of Z. tenuissimum. Cells 

 many times as long as broad. Sporangia oval, lodged in 

 much inflated cells. 



Hab. Cheshunt : A. H. H. 



This possibly may not be distinct, but prove eventually to 

 be the unconjugated state of Z. tenuissimum. 



