Reviews — Dr. Andrews — Marine Reptiles, Oxford Clay. 219 



would be of service to those who want to gain readily a general 

 knowledge of the geologj-. It is a curious fact that, despite the detail 

 concerning the rocks, no particulars are given in the text of the 

 fossils determined by Dr. Kayser and Dr. Henry Woodward, as 

 acknowledged in the Director's preface. 



The contemporaneous igneous rocks include sheared lavas and tuff 

 in the Lower Devonian, schalsteins and diabases in the Middle 

 Devonian, and vesicular lavas and tuffs of the spilite (pillow-lava) 

 type, also diabases, in the Upper Devonian. The intrusive rocks 

 include a large tract of granite forming the southern part of 

 Dartmoor with the Lee Moor china-clay works; also felsite, rhyolite, 

 granophyre, and some basic rocks. Considerable interest attaches 

 to the metamorphic aureole which borders the granite, the altered 

 rocks being described by Mr. George Barrow. Certain banded 

 siliceous and slaty rocks, which appear originally to have been 

 carbonaceous shale's and grits, are grouped by Mr. Ussher with the 

 Culm-measures. Less certainty arises with the grouping of tracts 

 of calc-flinta, which might be Devonian or Carboniferous. These 

 hard flinty rocks, according to Mr. Barrow, have resulted from the^ 

 alteration of calcareous sediments by pneumatolytic action, and there 

 have been developed in them such minerals as axinite, garnet, 

 datolite, etc. Dr. Teall has contributed some notes on the subject 

 (not, however, indicated in the text). Allusion is made to the 

 possible occurrence of a ' New Red Sandstone ' deposit, which was 

 originally noted by Sedgwick and Murchison, but is now so much 

 obscured by rainwash and talus that no confirmation of the 

 occurrence can be given. Some relics of Tertiary, possibly Eocene, 

 strata are described ; then follow short accounts of the cavern 

 deposits, head, river gravels, rock valleys and deposits below high- 

 water mark, submerged forests and peat. In the chapter on 

 Economies the subjects include water supply, metalliferous mines 

 (with notes by Mr. D. A. MacAlister), china clay, building-stone, 

 marble, road-stone, slate, lime, peat, and soils. 



The plates are good, notably that of an elvan in Upper Devonian 

 slate at the Cann Quarry ; and, needless to say, the colour-printed 

 map Sheet 349 (price Is. Qd.) is excellent, and well shows the great 

 progress made by tlie Geological Survey, and by Mr. Ussher in 

 particular, in elucidating the structure of South Devon. 



III. — A Descriptive Catalogue op the Marine Reptilia of the 

 Oxford Clay, based on the Leeds Collection in the British 

 Museum (Natdral History), London. Part II. By Charles 

 William Andre^vs, D.Sc, E.R.S. 4to ; pp. i-xxiv and 1-206 

 (including index), with 73 text-figures and 13 plates by Miss 

 G. M. Woodward, and collotype frontispiece. Printed by order 

 of the Trustees of the British Museum by Taylor & Erancis, 

 London, 1913. Price 25s. 

 rpHE appearance of the second volume of this Catalogue calls for the 

 J_ heartiest congratulations to all those responsible for the pro- 

 duction of this highly valuable work. It must certainly be reckoned 

 among the most important works of reference that have emanated from 



