160 PBOF. J. E. HAKKISOy OX EXTBAXEOUS [vol. lxxv,. 



The origin of the constituents of the red earth prior to their 

 incorporation in the coral-rock was not discussed by us. At the- 

 time we regarded the absence of defined beds of volcanic debris,, 

 such as are of very frequent occurrence in the Oceanic Series (for 

 instance, the Conset's-Gully section supplies evidence of over 

 fifty volcanic outbursts, each of which must have far exceeded in 

 intensity any of the historically-recorded ones), as an indication 

 that volcanic activity in the vicinity of the rising coral-limestone 

 island was reduced to a minimum in that long period which 

 elapsed from the Pliocene to geologically-speaking comparatively 

 recent times, during which the limestones were being built up ; 

 but, in a field-address T on the Geological Formation of Barbados 

 delivered in that island in January, 1908. I said : — - 



6 Beds of volcanic dust occur at short intervals all through the Oceanic 

 deposits and are characteristic of these strata in Barbados. I have not 

 recognized any beds of volcanic debris in the older underlying Cretaceous and 

 Oligocene strata or in the overlying Coralline ones. But this may be due to 

 these being strata which were deposited in wave-and- current disturbed, 

 shallow water, so that any volcanic dust which may have fallen on them 

 would be widely distributed throughout them, and would not occur in thin 

 seams as they do where they were deposited at the bottom of the calm, almost 

 motionless, depths of the ocean.' 



Soon after the eruption of the St. Vincent Soufriere in 1902, 

 the Consulting Chemist to the Barbados General Agricultural 

 Society, Mr. George Hughes, F.C.S., suggested that Barbados 

 derived its soils, if not altogether, at any rate largely, from falls of 

 volcanic dust blown over, similarly to those which had fallen in 

 that year, during eruptions of the West Indian volcanoes, but he 

 did not raise the question as to the origin of the acid-insoluble or 

 weathering residua of the coral-rock. 



Xo beds of volcanic debris have been found in the coral-lime- 

 stone, nor is it probable that such beds exist. These limestones 

 were formed, as are the coral-reefs at present encircling much of 

 the island, in shallow water with innumerable shifting currents 

 caused by the prevailing winds, the rise and fall of the tides and 

 the waves, and especially the breakers of the Atlantic Ocean. 



Any fall of volcanic ash, therefore, would not accumulate as a 

 definite bed in the limestone, but its materials would be dissemi- 

 nated over the growing corals, the lagoon- and channel-deposits 

 and the beach-limestones in course of formation, while by far the 

 greater part would be washed away into the surrounding deeper 

 Avaters. 



Probably the most enthusiastic collector of paheontological and 

 geologieal specimens avIio has resided in Barbados, was the late 

 G. F. Franks. Among the specimens that Franks left to me were- 

 a series of fragments of reef-corals, valueless from a paheontological 

 point of view ; but duplicates of these he sent to Prof. J. W. 

 Gregory in 1892, and they were described by the latter in his paper 

 on the ' Palaeontology & Physical Geology of the West Indies ' 2 ; 



1 West Indian Bulletin, vol. ix (1909) pp. 283 & 284. 



2 Q. J. G. S. vol. li (1895) pp. 257-85. 



