40 Reports and Proceedings— 
there are rocks soluble in water, such as rock-salt and gypsum, and 
the carbonates, which require the aid of free carbonic acid in the 
waters, rocks whose decomposition produces soluble matter such as 
pyrites, ete., etc. Also water charged with saline matter probably 
possesses greater solvent powers over certain substances. The 
author then considers the principal elements and source of these 
compounds in succession in a tolerably long chapter. 
In a fourth book Mons. Daubrée makes some general observations 
relative to the subject, and especially discusses the origin of the 
temperature of underground waters. Again he illustrates the 
subject with numerous sections, showing from instances culled in 
all directions how the result may be influenced by plications of the 
strata at high angles, whereby the waters are drawn down through 
synclinal folds to depths where considerable elevation of temperature 
obtains. Even extinct volcanoes, and rocks of volcanic origin, such 
as basalts and trachytes, retain sufficient heat to influence the waters 
which percolate them. Asia Minor, for instance, is a country 
exceptionally rich in thermal springs. The subject of geysers and 
voleanoes is again resumed. With regard to the latter, Mons. 
Daubrée quotes Mr. W. L. Green, who bas studied the Hawaiian 
volcanoes, to the effect that in the eruptions of that archipelago the 
vapour of water has only played a secondary part. This is an 
important quotation in view of M. Daubrée’s previous assertions 
with respect to the functions of underground waters in these 
phenomena. It also bears upon a question which has of late much 
engaged the attention of Prof. Prestwich and other writers. Lastly, 
Mons. Daubrée discusses the part which water may play in earth- 
quakes. 
An index of subjects, a second of localities, and a third of anthors, 
accompanies the work, which, although having no special claim to 
originality, constitutes a valuable text-book on the question of under- 
ground waters, considered under almost every aspect which can well 
be conceived. For geological purposes it also affords a good intro- 
duction to the companion work already noticed, whici is likewise 
provided with copious indexes. 
W. H. H. 
Asal Ones) AID ey @ CASED Ness 
—$<——— 
GeroLocicaL Society or Lonpon. 
November 23, 1887.—Prof. J. W. Judd, F.R.S., President, in the 
chair.—The following communications were read :— 
1. “Note on a New Wealden Iguanodont, and other Dinosaurs.” 
By R. Lydekker, Esq., B.A., F.G.S. 
The new species of Iguanodon was founded upon a left ilium and 
ischium, parts of the pubis and tibia, two metatarsals, several dorsal 
lumbar and caudal vertebree and other bones, obtained by Mr. 
C. Dawson, F.G.8., from the Wadhurst clay of the Hastings Sand. 
The species now described, which was named after the discoverer, 
