Since the defcription of C. fpiralis was written, and indeed the whole fafciculus 

 finifhed, I have had an opportunity of tracing its growth fatisfaftorily,* and of afcer- 

 taining that it is not C. nitida in a younger ft ate; but was furprized to find that in the 

 laft ftage of its exiftence, the filaments became connected in a manner precifely 

 refembling C. jugalis, which ftrengthens the fufpicion that that curious plant is 

 not a diftind fpecies, but only an appearance affirmed by C. nitida in certain filia- 

 tions, or at certain periods of its growth ; the fame circumftance will probably be 

 found in fome other fpecies of this Angular tribe. 



A. C. fpiralis magnified I. 



B. Ditto anaftomozing after the manner of C. jugalis, magnified i . 



# May 2d, I found C. fpiralis growing abundantly in a pool near Yarmouth, in which I obferved 

 none when I examined it but a few days before; the filaments were then as reprefented in fig. 4. 



May 6th, The plant occupied a larger fpace in the pool, but when magnified ftill appeared the fame. 



May 10th, The plant was of a more dull colour and had loft fome of its lubricity, and when ex- 

 amined under a microfcope, many of the filaments were feen connected, as reprefented in fig. B. they 

 differed from C. jugalis only in the difpof.tion of the feeds, being fingly fpiral in their fmaller fize, and 

 in the oval manes not appearing fo denfe in thofe joints wherein the granules had collapfcd. 



May . 3 th, The whole was in a ftate of decay, but all the joints which ftill retained the fpiral dif- 

 pof.tion of the granules, had that difpofition only fingle ; and though I examined a great number of 

 filaments at each of the times above mentioned, 1 could not find one in which they were at all other- 

 wife. This fudden appearance and difappearance of the Conferva had been before obferved by my 

 friend D. Turner ; who, in the Introduction to his Synopfis, p. 19, obferves, that often when he has 

 known ditches filled with particular fpecie,, he has returned after a ihort time and found not even 1 

 veftige oftheinleft. 



