Reviews — The Palceontographical Society. 421 



igneous intrusion outcrops on Sourton Tor and on the high ground 

 north of it, -where it is of a porphyritic type, like that seen at Skaigh, 

 and apparently on the same horizon. 



NOMENCLATURE. 



For convenience of reference it may be well to give local names to 

 the rocks that have been dealt with in these pages. The rapidly 

 alternating shaly and gritty rocks, so well seen along the Okement 

 at Ball Hill and in the Simmons Park, may appropriately be named 

 the Okehampton Beds. The underlying strata, to which most attention 

 has here been devoted, and which are essentially a calciferous shale 

 series, are perhaps best termed Sticklepath Beds. Their upper limit 

 may be defined as the point where the gritty bands first make their 

 appearance. The series itself is, so far as I have been able to see, 

 entirely free from grit. The base is that of the shales which in the 

 metamorphic area are represented by andalusite hornfels. They 

 appear to rest near Lake 1 on beds of which a considerable thickness 

 is gritty throughout, as seen near the railway at Lake and Southerley, 

 though they include sharply folded (? radiolarian) rocks near 

 Lake Viaduct, banded calcareous shales east of Southerley, as well as 

 the purer shales represented by the andalusite hornfels of Great 

 Nodden, where a seam of limestone and some grit bands also occur. 

 These Southerley Beds, as they may be termed, rest on the By d ford 

 Beds, which have at their top the Downtown calc-flinta. They are 

 essentially, however, a thick succession of shales of the type which 

 are rather chloritic than strictly argillaceous in character, and are 

 represented in the contact zone almost exclusively by cordierite 

 hornfels. 



Before concluding, it is both a duty and a pleasure for me to 

 acknowledge the constant aid and frequent companionship of my 

 friends Dr. E. H. Young and Mr. H. J. Ward, of Okehampton, 

 during the investigation of the interesting rocks which form the 

 subject of this paper. 



REVIEWS. 



I. — The Pal^ontographical Society. Vol. LXXI, April, 1919. 

 Volume issued for 1917. 4to ; pp. 170. Printed for the 

 Society. Agents for the Society, Dulau & Co., Ltd., 

 34-36* Margaret Street, W. 1. 



THE volume issued this year, although lacking in its usual 

 bulk, owing to the further rise in printers' prices and the 

 general shortage of paper, etc., does not suffer as to the quality 

 either of its printed matter, its plates, or the authors' contributions 

 of valuable text. 



1. Dr. Arthur Smith Woodward presents part iii (the concluding 

 part) of his monograph on the Fossil Fishes of the English Wealden 

 and Purbeck Formations (pp. viii, 105-48, and 12 pages of explana- 

 tion of pis. xxi-vi). The text also carries seven additional 



1 There are probably several faults or thrusts about here. 



