434 Mr. HassalPs Notices of British Freshwater Conferva, 



The above appears to be one of several species which have 

 all been confounded under the name of M. genuflexa. 

 Vicinity of Cheshunt. 



Mougeotia quadrangulata. Filaments of less diameter than 



those of M, caerulescens ; cells usually six times as long as 



broad; sporangium quadrangular. 



This very interesting species I for a long time confounded 

 with the M. caerulescens of Capt. Carmichael, an error which 

 I was enabled to correct through the kindness of Mr. Ralfs, 

 from whom I have received more than one fine specimen of 

 that production. 



The present species differs from M. caerulescens in having 

 finer filaments as well as in the form of the sporangium. In 

 M. caerulescens the sporangium is somewhat cruciform, while 

 in M. quadrangulata it is quadrangular. 



Found in the early part of the spring of the past year (1842), 

 at High Beech, Epping Forest. 



Mougeotia parmla. Filaments as slender as those of V. bom- 

 bycina ; cells usually six times as long as broad ; endo- 

 chrome imperfectly divided into two roundish masses ; 

 spores circular, lodged in the transverse tubes. 

 I at first regarded the above species as the Zygnema ordi- 

 narium of the Rev. M. J. Berkeley, but that gentleman informs 

 me that the filaments of his species exceed in diameter those 

 of Z. elongatum, a much more robust Conferva than mine. 

 Vicinity of Cheshunt. 



Vesiculifera vernalis. Filaments more robust than those of 

 V. Mulleri ; cells usually six times as long as broad ; spores 

 circular, contained in inflated cells, which are somewhat 

 narrower at one extremity than the other. 

 This species, which I have twice found since the commence- 

 ment of the present year (March 4th, 1843), once at High 

 Beech and again near Waltham Abbey, approaches very closely 

 to V. Mulleri, from which it may be known, however, by its 

 stouter filaments as well as the less regularly spherical form 

 of the seed-bearing cells. 



Genus Sphjsroplea. 



Since the publication of my papers on the Vesiculasperms, 

 in which some remarks occurred relative to the reproduction 

 of the genus Sphaeroplea, I have received some very interest- 

 ing observations respecting one of the species of that genus 

 from Mr. Ralfs of Penzance, which I cannot do better than 

 transcribe in the writer's own words. 



* I believe you to be quite correct about the Vesiculaspernue, 



