262 Zoological Society. 



result of chemical science only^ and not the natural condition o 

 the bodies in question. We can only therefore regard the idea 

 of Brongniart as a pure hypothesis, which is very much easier to 

 invent than it is to carefully work out the truth by laborious in- 

 vestigation. 



And again, let me ask, what is the necessity for resorting to 

 far-fetched hypotheses to account for the presence of the si lex, 

 when we have such frequent and obvious evidences of its great 

 prevalence in solution in water under almost every description 

 of circumstances ? We have but to examine wheaten straw to 

 be assured of its having been imbibed by the plant from the 

 water of the soil during its growth and secreted as one of its 

 component elements in great abundance ; and every little boggy 

 hole that is filled with water, every pond, ditch, lake, river or sea, 

 swarms with Desmidise and infusorial animalcules alike secreting 

 silex as their outward covering and protection, evincing in all 

 these situations the abundance of the earth in question in solu- 

 tion ; and geology is proving to us daily that such also has been 

 the case from time immemorial. No vast pressure, no high 

 temperature is in reality required to sustain silex in solution, 

 and this is readily to be proved by reference to springs in our 

 own country, as at Bath, where the hot-bath spring yields 

 128 gallons of water per minute, or 184,320 gallons per day; 

 and as each pint of the water, according to the analysis of Mr. 

 R. Phillips, contains one-fifth of a grain of silex, there is conse- 

 quently 35| pounds of solid silex poured forth in solution in 

 every day's discharge, or 12,857 lbs. per annum, and the water 

 has a temperature of only 117° Fahr. The Great Geyser in Ice- 

 land jets forth a column 200 feet high and 10 feet in diameter 

 at a boiling temperature, and contains, it is said, 31*38 grains 

 of silex per gallon. If these two comparatively insignificant 

 sources produce thus much of silex, ought we to be at all either 

 surprised or astonished at the universal presence of this earth in 

 solution ? 



PROCEEDINGS OF LEARNED SOCIETIES. 



ZOOLOGICAL SOCIETY. 



December 8, 1846.— George Gulliver, Esq., F.R.S., in the Chair. 



A paper was read containing descriptions of 38 new species of 

 Land-shells, in the collection of Hugh Cuming, Esq., by Dr. L. 

 PfeifFer :— 



1. Parmacella Cumingi, Pfr. Parm. testd depresso-semiovatd, 

 tenuissimd, striatd, lineis spiralibus suhtiliter decussatd, diaphand. 



