——- — san 
Organic Matter found in Sulphureous Springs. 595 
Mr. Dillwyn adds, in a private communication with which he 
has favoured me, that he has since found Conferva nivea abun- 
dant in the hot springs about Aix la Chapelle, especially near 
Frankenburg. 
I leave it to the many better judges of such matters, than 
myself, that are to be found among the members of this So- 
ciety, to pronounce, whether the body, whose appearances under 
the microscope are faithfully depicted in the accompanying 
drawing, approaches near enough to the characters of Dillwyn's 
Conferva nivea to be regarded as the same, or as an allied spe- 
cies. To this, the want of resemblance as to colour must not be 
regarded an objection ; for the specimen I obtained at Digne, 
which appeared under the microscope to be the same kind of 
Oscillatoria as the one alluded to, was perfectly white; and 
M. Longchamp, in his treatise on the Waters of Vichy, informs 
us, that what he collected at Bareges was originally white, but 
became green when kept for a few days*, so that the discre- 
pancy as to colour ought not to be looked upon as establishing 
a distinction of species. Neither will the difference of tem- 
perature between the sulphureous water of Harrowgate and of 
Greoulx be considered inconsistent with the notion of the same 
Conferva growing in both, when we are reminded that it has 
also been found by Mr. Dillwyn himself in the thermal waters 
of Aix la Chapellet. 
At all events, it must be considered as a curious circumstance, 
that springs, of whatever temperature, which give out sulphu- 
* This change also took place very ro aa in the C, nivea a I collected at 
Croft in Yorkshire this autumn. 
+ Dr. Hooker found close to the edge of the inca’ in Tatar, and within a few 
inches of the boiling water, Conferva limosa, Dillw., a new species of Oscillatoria, 
and the finest specimens of Jungermannia angulosa he ever saw. In water, also, of 
a very great degree of heat, were, both abundant and luxurious, Conferva flavescens of 
Roth, and a new species allied to C. rivularis. 
retted 
