No. 431. New Series.— Decade IV.— Vol. VII.— No. V. Price Is. 6d. nett. 



THE 



GEOLOGICAL MAGAZINE 



onthli) Jaiuiual of (Seologij. 



WITH WHICH IS INCORPORATHD 



'*TME OKOLOGhlST." 



EDITED KY 



HENRY WOODWARD, LL.D., F.R.S., F.G.S., &c. 



ASSISTED BY 



ROBERT ETHERIDGE, F.R.S. L. & E., F.G.S., &c., 



WILFRID H. HUDLESTON, M.A., F.R.S. , F.L.S., F.G.S., &c. 



GEORGE J. HINDE, Ph.D., F.R.S., F.G.S., &,c., and 



HORACE BOLINGBROKE WOODWARD, F.R.S., F.G.S. 



MAY, 1900. 



O O IST T E InT 



I. Original Articles. 



PAGE II. Reviews. 



1. Studies in Edrioasteroidea. II. 

 lidrioaster BuchiunHS Forbes 

 sp. By F. A. Bather, M.A., 

 F.G.S. (Plates VIII, IX, and 



X; and 7 AVoodcuts.) 193 



2. Bala Lake and the Eiver 

 System of North Wales. By 

 Philip Lake, M.A., F.G.S. 

 (With 5 Woodcuts.) 204 



3. Plant-stems in the Guttannen 

 Gneiss. By Prof. 'J'. G.Bonkey, 

 D.Se., LL.D., F.R.S 215 



4. The Geological Age of the Earth. 

 Bv Prof. J. JoLY, M.A., D.Sc, 

 F.R.S 220 



5. Catalogue of the known Fora- 

 minifera from the Chalk, etc., 

 of S. and S.E. of Flngland. By 

 Prof. T. Rupert Jones, F.R.S., 

 F.G.S 225 



1. Professor James Hall & John M. 

 Clarke on Palaeozoic Reticulate 

 Sponges of the P^amily Dictyo- 

 spongidoe 230 



2. Prof. K. A. von Zittel's English 

 Edition of his Text- Book of 

 Pala?ontology 232 



3. Prof. E. Ray Laukester : A 

 Treatise on Zoology.. 233 



4. Memoirs of the Geological 

 Survey 234 



III. Reports and Proceedings. 

 Geological Society of London — 



1. February 21, 1900 236 



2. March 7, 1900 236 



IV. CORKESPONDENCE. 



1. The Rev. G. F. Whidborne, 

 M.A., F.G.S 239 



2. The Rev. J. F. Blake, M.A., 

 F.G.S 239 



LONDON: DTJLAU & CO., 37, SOHO SQUARE. 



(^ The Volume for 1899 of the GEOLOGICAL MAGAZINE is ready, 

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