392 Dr. Wheelton Hind — Loicer Culm of North Devon. 



like rottenness, and the schist, as implied on p. 12, is in good 

 condition close to the very outside. The state of the surface 

 suggests that mechanical forces may have co-operated with chemical, 

 for it is not unlike tliat produced by blown sand ; yet to gouge out 

 some of these, for instance that first described, the winds would 

 have to eddy in a very queer fashion, for the holes occasionally 

 run deep into the rock both sideways and upwards. Nor does the 

 action of dew or of moisture in any form seem a promising explana- 

 tion, for they occur on both sheltered and exposed sides of the 

 blocks and look to all points of the compass, though more commonly 

 westwards. 



This brings me to the difficulty, which, owing to ray general 

 knowledge of Corsica and Mr. Tuckett's descriptions, had prevented 

 me from seeking an explanation in Indian or any other desert regions. 

 Its scenery, so far as I know it, is at least as luxuriant as that 

 around the subalpine Italian lakes. There was not a trace of grit 

 or sand about the Ajaccio blocks, and to reduce an island in this 

 part of the Mediterranean to the conditions of a desert or steppe 

 would demand changes of geography or climate which are almost 

 startling, and we must also suppose that since the arid epoch 

 ended tlie surfaces of the hollows have undergone little or no 

 alteration. Neither atmospheric corrosion nor any form of wind 

 abrasion seems to satisfy all the conditions of the problem, and 

 vmtil I can spend some time in Corsica to study other examples 

 I prefer to restrict myself to this statement, negative though it be. 



III. — On the Homotaxial Equivalents of the Lower Culm of 



North Devonshire. 



By Wheelton- Hind, M.D., B.S., F.R.C.S., F.G.S. 



IN the paper on the Pendleside group at Pendle Hill, Q.J.G.S., 

 vol. Ivii, p. 377, I said, " The further facts of the distribution of 

 Glyphiocevas spircde and Posidonomya Becheri set forth in the fore- 

 going pages open up the wide question of the age of the Culm beds 

 of Devon and Germany." Since then I have had the great advantage 

 of examining suites of fossils from the Lower Culm of Devonshire, 

 collected b}' Mr. Hamling, of Barnstaple, and Mr. Coomjuaswamy, 

 from the Coddon Hill Beds and other localities in North Devon. 

 I was so interested in the fossils that I found it necessary to 

 go down and examine the beds in which they occurred, and 

 Mr. Hamling gave me the inestimable advantage of his guidance. 

 In this way we examined the Lower Culm and the underlying 

 Pilton Beds in detail from West Leigh to Fremington, and the 

 so-called Middle Culm of Bideford and other places. I was able 

 to see the Hall collection of fossils at Barnstaple, and again to 

 renew my acquaintance with Mr. Hamling's collection. This visit 

 to Devonshii-e, it seems to me, was fortunately planned after a visit 

 last Summer to the Devono-Carboniferous succession in the south- 

 west of Ireland, and a study of the fauna in the collection of 

 the Geological Survey at Dublin and in the Museum of Queen's 

 College, Cork. 



