Notices of Memoirs — R. G. Symes, Geology of Clermont. 563 

 nsroTioiES OIF nvniE^vcoiiRS. 



I. — The Geology and Extinct Volcanos of ClekmonT; 



AUVERGNE.^ 

 By EicHARD G. Symes, F.G.S. 



ME. SYMES having visited this district in the summer of 1870^ 

 in company with Mr. Leonard, gives us an interesting paper, 

 the results of their observations on the Plutonic, Aqueous, and 

 Volcanic rocks. The country chiefly examined was that between 

 four and five miles west of Clermont, The granite is described as- 

 generally consisting of two micas (margarodite and lepidomelane, 

 the latter predominating in nearly every case over the former), one 

 felspar (oligoclase) and glassy quartz. It was found to decompose 

 the more readily as it approached Volcanic rocks. The Aqueous 

 rocks, of Upper Eocene or Miocene age, are briefly described as 

 consisting of grits, marls, and indusial limestone or travertin. The 

 grits are for the most part composed of the debris of granite and 

 basalt, bound together by a siliceous cement. Mr. Symes obtained 

 a specimen containing a well-rounded pebble of basalt: a fact 

 of some importance, as Scrope and Lyell remark that no traces 

 of volcanic rocks occur in these beds. In regard to the volcanic 

 phenomena, the inferences drawn are : that the condition to which, 

 the volcanos are referable is that in which eruptive j)aroxysms 

 of intense energy alternate with lengthened periods of complete 

 inertness ; that the cinder cones, Domitic hills, and recent lavas are 

 all due to one violent paroxysm spread over an area twenty miles 

 long by two broad ; that the presence of two such different rocks as- 

 basalt and trachyte, in close juxtaposition, can only be accounted for 

 on the supposition that the rocks from which they are derived, 

 namely, hornblende rock and some highly felspathic rock, such as 

 granite, were in contact prior to their being reduced to the forms we 

 now find them in ; that the granite plateau was very much in the 

 same condition prior to the deposition of the lacustrine strata, as it 

 is now; that prior to the deposition of the lacustrine strata, this 

 district was probably the seat of volcanic eruption^ 



II. — On Ehrbnberg's Eokaminifera from the Chalk of Meudon„ 



France. 



By Prof. T. Eupert Jones, F.G.S., and W.. K. Parkee, F.R.S. 



IN No. 89 of the Gteological Magazine, p. 511, we indicated the 

 genera and species of Foraminifera found by Dr. Ehrenbero^ 

 in the White Chalk of Meudon, near Paris, and figured ui his 

 " Mikrogeologie," 1854. 



In our list twenty species were enumerated (with the nomen- 

 clature now in use) as the result of our study of the fifty-six forms 



^ A paper read before tlie Eoyal Geological Society of Ireland, April 12, 1871. 



