TYNDAEIDEA. 163 



circular, contained within the cells. Cells usually rather 



more than tivice as long as broad. 

 Tyndaridea hicornis, Annals of Nat. Hist. vol. x. p. 43. 

 Hab. Cheshunt and other places : A. H. H, 



This species is by no means uncommon, and is certainly 

 distinct. A species described in the 10th vol. of the Annals 

 of Nat. Hist, under the name of T, iyiterposita, ought, I think, 

 to be regarded as a variety of the species. Fig. 8. plate 

 XXXVIII. may perhaps represent a species distinct from T. 

 bicornis. I have more than once met with it just as repre- 

 sented in the figure. 



5. T. INSIGNIS Hass. 

 Plate XXXVIII. Figs. 6, 7. 



Char. Filaments rather smaller than those of T. bicornis. 

 Cells ttvice as long as broad, and frequently curiously 

 distorted, that side of them tchich either has or is about 

 to unite itself ivith another, becoming remarkably protube- 

 rant. Sporangia circidar, and partly lodged in the trans- 

 verse tubes. 

 Hab. High Beech, Wanstead, and other places : A. H. H. 

 Rusthall Common ; in a pool by the road-side between 

 Cross in Hand and Heathfield ; pond near Five Ashes, 

 INIayfield ; on Watcrdown Forest ; Greatham and 

 Storriugton Commons : Mr. Jenner. 



This species, which sometimes presents an appearance so 

 remarkable, was first sent me by JNIr. Jenner. It is by no 

 means uncommon, and I think certainly distinct from all 

 others with which I am acquainted. 



6. Tyndaridea stagnalis Ilass. 



Plate XXXVIII. Fig. 9. 



Char. Filaments more slender than those of T. insignis. Cells 

 about two a?id a half times as long as broad. Sporangia 



