436 Mr. Hassall's Notices of British Freshwater Conferva, 



sketches of his and my plants, and against his sketch is written 

 " the granules separate into most active Zoosperms." Thus 

 (supposing the Conferva bicolor to be the same) we have three 

 different observers noticing the motion in this plant, neither 

 of us being aware at the time of its having been noticed by 

 the others 7? 



If there be no fallacy connected with the above highly in- 

 teresting remarks, and it can scarcely be supposed that there 

 is any, since the singular motion of the granules into which 

 each of the larger masses found in Sph. crispa is said to se- 

 parate, is not only attested by so many able observers in our 

 own country, but was likewise especially witnessed in this 

 same species by Agardh himself, for the Conferva zonata, one 

 of the three species more particularly submitted by him to ex- 

 amination is assuredly none other than the Conferva bicolor of 

 6 English Botany/ and this again, it is equally certain, is the 

 Sph. crispa of the Rev. M. J. Berkeley as well as Conferva 

 lucens of Mr. Dillwyn. It would appear that I have erred in 

 regarding the large condensed masses of endochrome found in 

 the cells of C. zonata as true spores, an opinion which I at no 

 time entertained without a degree of misgiving. Nevertheless I 

 still think that I am correct in ascribing the formation of these 

 masses to the intermingling of the contents of adjacent cells 

 in the same filament, whereby fecundation may be supposed 

 to be effected, and which intermingling I have shown to occur 

 so invariably in the Vesiculaspermce*. 



The only undoubted species which can at present be referred 

 to the genus Sphceroplea is the Conferva zonata of Weber, and 

 this would appear to present a threefold relation with other 

 freshwater Confervae ; first, with the Conjugates in the excessive 

 mucosity of its filaments ; secondly, with Vesiculasperms in its 

 attenuated filaments and in the intermingling of the contents 

 of two cells ; and lastly, with the branched Confervae in the 

 other particulars of its reproduction, amongst the species of 

 which group it should find its station. 



The following species, if not to be regarded as a Sphceroplea, 

 should be referred to the genus Lyngbya, and which differs 

 but slightly, and perhaps not in any material respect, from 

 Sphceroplea. 



Sphceroplea ? vermicularis. Filaments very mucous, floating, of 

 a light green colour, in diameter but little exceeding those 

 of Vesiculifera bombycina ; cells usually not quite so long 



* I am now able to add my own testimony to the correctness of the above 

 remarks. In my specimens, however, the synspores did not escape at the 

 top of the filament, but by apertures in the cells occasioned by their bursting. 



