November 28, 1907] 



jV.4 TURE 



91 



porphyry which traverse the district, and are of sliglitly 

 later date than the granite. Fifty-seven pages are devoted 

 to economic geology and mining, much information being 

 given about the mineral lodes and the mines, some of 

 which are now being re-opened. 



Brief accounts are given of the Pliocene deposits of 

 St. Erth and of the later Pleistocene accumulations. 



The photographic views are clear and well repro- 

 duced, as may be seen from the example here given. 

 The map is well printed on good thick paper, and the 

 only fault we have to find with the colouring is that the 

 tints indicating Pliocene and Valley Gravel are barely 

 distinguishable from one another. 



(2) The second memoir deals with an area which includes 

 parts of Berkshire, Wiltshire, and Hampshire, the larger 

 portion being in Berkshire and traversed by the valley of 



found in two small outliers, which are due to shallow 

 synclinal flexures. 



By aid of this zonal work Mr. White is able to show 

 the e.xact nature and extent of the unconformity between 

 the Chalk and the Eocene. This proves to be a gradual 

 overstep, the Eocene passing transgressively on to older 

 and older beds in a northerly direction. Hence it would 

 seem that, prior to the Eocene sedimentation, the whole area 

 had a continuous slope from north to south, and that the 

 Kingsclere-Pewsey anticline is entirely of post-Eocene date. 



Chapters are devoted to the Reading beds, the London. 

 Clay, the Lower Bagshot beds, the Clay-with-Flints, the 

 Plateau Gravel, the valley gravels, alluvium, and 

 economics. There are also appendices on the MoUusca 

 of the alluvium of the Kennet by Messrs. .A. S. Kennard 

 and B. B. Woodward, and on the insoluble matter in- 



Mew of the soulh side of the Land's End. F 



the Kennet. Nothing older than the Selbornian (Upper 

 Greensand) reaches the surface, and the greater part is 

 occupied by Chalk, Eocene beds, and Clay-with-flints. The 

 colouring of the map is clear, and the paper on which it is 

 printed is thicker than that of sheets issued in previous 

 years. 



It is some time since this area was surveyed, and in the 

 meantime Mr. Osborne White has made a detailed study 

 of the Chalk and its zones in Berkshire, as well as of the 

 superficial deposits of this and neighbouring districts, so 

 that the preparation of the memoir could not have been 

 put into better hands. 



Of the Cretaceous rocks described, the chief interest 

 centres in the Upper Chalk, which is dealt with zone by 

 zone : two of these, the zone of Marstipiles tcstudiiiarius 

 and that of Actinocama.x quadratus, have onlv been proved 

 to exist in Berkshire within the last three' years. The 

 former has a continuous outcrop from the western border 

 as far east as Newbury, and this outcrop is indicated on 

 a sketch-map in the memoir ; but the higher zone is only 



NO. 1987, VOL. yy] 



11 " The Geology of the Land's End District." 



samples of Upper Chalk by Dr. W. Pollard and Mr. 

 H. H. Thomas. Finally, the memoir is furnished with a 

 bibliography and a good index. 



RECENT PUBLICATIONS OF THE U.S. . 

 MUSEUM.' 

 'T'HE subjoined list (which is exclusive of a large 

 number of minor publications) affords a striking ex- 

 ample of the energy with which scientific research is 

 being pushed in America, a noteworthy fact being that, 

 1 (1) "The Birds of North and Middle America." Part iv. By R. 

 Ridgway. Bull. U.S. Nat. Museum, No. 50. Pp. xxii+973. 



(2) '* Catalogue of the Type and Figured Specimens of Fossils, Minerals, 

 Rocks, and Ores in the Department of Geology, U.S. Mus." Part ii. By 

 J. P. Merrill. ('/. cil., No. 51. Pp. v-t-37o. 



(3) "The Families and Genera of Bats." By G. S. Miller. Op. ci 

 No. 57. Pp. xvii + 2S2. 



(4) " Herpetology of Jaoan and Adjacent Territory." By L. Stejneger 

 Op. cit.. No. 58. Pp. XX + S77. 



(5) "Report on the Diatoms of the Aibatross Voyages in the Pacific 

 Ocean, 1888-1904 " By Albert Mann. Conlr. U.S. Nat. Herbarium, vol. x., 

 part V. Pp. V-I-22I-424. 



