Vol. 51.] AND PHYSICAL GEOLOGY OF THE WEST INDIES. 311 



with three series of deposits — the Reefs, the Oceanic Series, and the 

 Scotland Beds — which owe their origin to varying age and very dif- 

 ferent depth of deposits. 



Mr. Mare, having obtained the President's permission, read the 

 following remarks made by Mr. Jukes-Browne (wbo was prevented 

 by ill-health from being present at the meeting) : — 



' As Dr. Gregory's paper deals with the relative ages of the rocks 

 in Barbados, I take the opportunity of communicating the results 

 of some investigations made by Mr. G. F. Franks, F.G.S., in the 

 neighbourhood of Bissex Hill. In the paper by Prof. Harrison and 

 myself, we stated that the higher part of this hill consisted of 

 granular Globigerina-m&rl capped by a limestone and marl con- 

 taining foraminifera, shell-fragments, and included pieces of chalk. 

 This we regarded as a separate formation, but classed the marl 

 below with the Oceanic deposits. Mr. Franks, however, has dis- 

 covered detrital limestones in the Globigerina-marls, as well as some 

 evidence which suggests that the whole mass of Globigerina-rock 

 lies unconformably upon the Oceanic Series, and is faulted down 

 into the centre of the Bissex Hill area. 



' Mr. Franks has not yet been able to find a clear and unfaulted 

 junction of the two formations, but, if his observations are correct, 

 the group of beds which we classed as of intermediate date between 

 the Oceanic Series and the Coral Rocks acquires a greater im- 

 portance. Moreover, it seems to be more intimately connected 

 with the Coral Reefs than with the Oceanic deposits, for Mr. Franks 

 has found patches of reef-rock on the spurs of the hill, which seem 

 to pass down into the upper shelly portion of the Foraminiferal 

 Marls. He has also discovered the same succession in a well-shaft 

 at Bowmanston. 



' In view of these facts, we are quite prepared to accept Dr. 

 Gregory's conclusion that the Oceanic Series is of Miocene age, the 

 more so as Dr. Spencer has come to the same conclusion with 

 respect to the Radiolarian Earths of Cuba, after a personal study of 

 the geology of that island. The Barbadian succession may there- 

 fore be provisionally stated as follows, and I hope that ere long I 

 may be able to lay the evidence for it before the Society : — 



P eistocene \ „. ," , . ,, „' 



j J High-level Reefs. 



T, r 1 Foraminiferal Marls and 



Pliocene. x . , 



l_ Limestones. 



Break. 

 Miocene = Oceanic Series. 



Break. 

 Eocene = Scotland Beds.' 



Mr. Clement Reid observed that, judging by the extent of post- 

 Oligocene denudation in Europe, it is unsafe to take the present 

 height of the Isthmus of Panama as any measure of its height in 

 Tertiary times. If the mountains were formerly much higher, it is 

 evident that great elevations and depressions might take place in 



