532 A. CHAMPERNOWNE AND W. A. E. USSHER ON THE 
41. Norss on the Srructure of the Patmozorc Districts of West 
Somerset, By A. Coamprrnowne, Ksq., M.A., F.G.S., and W. 
A. E. Ussurr, Esq., F.G.S. (Read May 14, 1879.) 
INTRODUCTION. 
Iw the following account of traverses made during the past autumn 
across some of the classical ground of West Somerset and its con- 
fines, we do not aim at any extensive alteration in principle of the 
work wrought by the master hand of De la Beche, and given to the 
scientific world forty years ago *. 
Notwithstanding the encyclopedic paper of Mr. Etheridge +, 
wherein both the physical and paleontological relations of the 
North-Devon rocks are so ably worked out, instances of unbelief 
will occur where ocular evidence is wanting, prompted perhaps by 
a hankering after the apparently simple version of the structure of 
North Devon put forward by the late lamented Prof. Jukes £. 
Although the ground has been carefully gone over in Mr. Kthe- 
ridge’s paper, such a confirmation of his views as the infilling of 
minor stratigraphical details affords may not be altogether unworthy 
of attention. 
The classification which De ia Beche’s unequalled description of 
the North-Devon rocks suggests was put into form by the late Prof. 
Phillips, who, however, included the unfossiliferous grits and slates 
of Pickwell Down with the slates of Mortehoe as one division §. 
Although these divisions were similarly treated by Mr. Hall in 1865 
and 1867 ||, a more detailed description mitigated an error of classi- 
fication which that gentleman has since abandoned. Mr. Hall in- 
formed us that the term Pickwell-Down Sandstone was applied to 
that division by Prof. Jukes, acting on his suggestion. To Mr. Hall 
belongs the credit of inaugurating the present more complete classi- 
fication, which rightly distinguishes the position of the Lower 
Pilton, or Baggy Beds in the upper part of the series]. This clas- 
sification was, with some slight modifications, retained by Mr. Ethe- 
ridge, and has been adopted by us. With this introduction, we 
shall commence with our westernmost traverses. 
* Report on Geol. of Cornw. & Dev. ch. 3, &e. 
t Q. J. G.S. vol. xxiii. p. 568. 
t Q. J. G. 8. vol. xxii, p. 320, and additional Notes, &e. 
§ Pal. Foss. Devon, Cornwall, and W. Somerset, pp. 183-193. 
|| Lecture to Exeter Naturalists’ Club, Sept. 23, 1865; and Q.J.G.8. 
yol. xxiii. p. 372, 
§| It should be mentioned that Mr. Hall has abandoned the term conglome- 
rate as applicable to any of the N. Devon Devonian rocks, the concretionary 
structure in the Pickwell Down division to which it was ’ applied being too 
insignificant to merit the designation. 
