Geological Society of London. 283 



of tbe centrum of the cervical vertebrae, proving the existence of 

 cervical ribs, and the character of the neural spine of a dorsal 

 vertebra which strikingly recalls that of a bird. 



4. "Notes on a 'Wash-out' found in the Pleasley and Teversall 

 Collieries, Derbyshire and Nottinghamshire." By J. C. B. Hendy, 

 Esq. Communicated by Dr. W. T. Blanford, F.R.S., F.G.S. 



Sections were given of the " Wash " showing the thickening of 

 the coal as it approaches the same, and the splitting of the " Wash " 

 itself into two branches. Various measurements were noted, and 

 certain disturbances recorded. In every section examined, the sides 

 of the " Wash " are more or less slickensided, and in some few cases 

 the coal is distorted next to the " Wash " ; but the author is of 

 opinion that these are due to lateral pressure and movement subse- 

 quent to the denudation of the coal and deposition of the sandstone, 

 and he remarks on the difficulty of reconciling the regularity of the 

 underclay with the theory of the formation of " Washes " by 

 disturbance. 



He considers that they are due, in Durham and elsewhere, to 

 currents flowing at a high rate of speed in one direction, carrying 

 away the denuded material, and, as in the case of the Derbyshire 

 " Wash," to a series of inundations, each inrush denuding a certain 

 amount, and on subsiding, redepositing part of the material at a 

 higher level, while the remainder was carried away in suspension. 



In conclusion, notice was taken of " washes " occurring in other 

 localities. 



II.— April 30, 1890.— Dr. A. Geikie, F.R.S., President, in the 

 Chair. — The following communications were read : — 



1. " On certain Physical Peculiarities exhibited by the so-called 

 ' Raised Beaches ' of Hope's Nose and the Thatcher Rock, Devon." 

 By D. Pidgeon, Esq., F.G.S. 



The author described the peculiarities of these so-called beaches, 

 including the absence of stratification, the presence of splinters of 

 rock like that of the overlying limestone cliffs, the scarcity of 

 rounded pebbles, and the great abundance of sharply fractured 

 shells associated with unbroken rock-dwelling shells. 



He enumerated the fossils collected from these deposits by Mr. A. 

 R. Hunt, which include Troplwn truncatus and Pleurotoma turricula, 

 and calling attention to the observations of Messrs. Feilden and 

 De Ranee, and of Dr. Moss upon the ice-foot of Arctic regions, and 

 the accumulation of material in the trenches found therein, concluded 

 that the deposits under consideration were formed at a time when a 

 small bay existed between Hope's Nose and the Thatcher Rock, 

 which has since been destroyed by denudation of the intervening 

 sandstone, in which bay an ice-foot once existed ; and further, that 

 the two deposits from the surviving relics of the mingled mass of 

 chips, shells, shell- fragments, Crustacea, etc., which must have filled 

 the trench in the ice-foot demanded in such a position. This would 

 place the time of formation of the deposits at the close of the 

 Glacial period. 



