66 MEMORANDA. 
portant physiological question, so that I feel justified in 
urging the subject upon all who have the materials at hand, 
the more so as little trouble will be found attached to it. 
Any results obtained would surely be communicated in these 
papers, and the writer of this would be deeply indebted to all 
who may furnish him with additional information on the 
subject. 
I am glad to he able to close these lines with an account of 
what I believe to be an encouraging new fact. Through the 
kindness of Dr. Abercrombie, of Cheltenham, I have just re- 
ceived a living gathering of Bacil/aria paradoxa from the 
Avon, above Tewkesbury, associated with such freshwater 
forms as are common iu every roadside ditch, Pleurosigma 
attenuatum, Nitzschia sigmoidea, Navicula gr acilis (£.), &e., 
and Encyonema prostraium. The unique Bacillaria is very 
plentiful, indeed, in this beautiful gathering, and continues, 
placed in common well water, in most energetic activity. 
NMitzschia dubia is also stated by the same gentleman, on the 
authority of Dr. Greville, to be frequent all around Chelten- 
ham, though it had no business there.” Lastly, our Home- 
ocladia filiformis, or a very similar species, is reported to be 
very abundant in the Severn, above Tewkesbury, thus afford- 
ing new evidence with respect to the great range of adapta- 
bility enjoyed in by these marvellous fairy gems ; and which, 
when properly foliowed up, will certainly not fail to throw a 
gleam of light on the obscure paths of physiological inquiry. 
at ee Evienstern, Stutgard. 
N.B.—The following errata eal be corrected in M. Kulenstein’s former 
communication (Vol. IV, p. 172 
Page 172, in line § from ate substitute a comma for the full stop. 
re Be gal: 5 for Berkeleyia, read Berkeleya. 
3 Np i) " » Drokreia »  Dickieia. 
Fe poe Wie my »» -Uastigloia ., Mastoglora. 
> ape e », Homacladia ,, Homeocladia. 
5 ny Sew: cs », Raphdogiea ,, Rhabdogloia. 
fv Bt ‘ » Honecladia ,, Homeocladia. 
Boge 173 * 5 Owhts » fiifliliformis ,, jiliformis. 
In the title of the paper, for Homaciania, read Homm@ocnapia; and the 
author’s initials are Th., and zof F. L. 
My, Goddard's Mounting Table—In the last number of the 
Journal, p. 296, Mr. Stokes, writing respecting my table, 
states that the balsam in which specimens are mounted is very 
