202 H. Dewey Sf Br. J. S. Flett— 



LitJiostrotion irregulare, Phill. Productus spines. 



L. junceum, Flem. Rlnjnclionella pleurodon, Phill. 



Zaplirentis sp. Aviculopecten sp. 



Crinoid ossicles (many large). Nucula gibbosa, Flem. 



Echinoid spines and plates. Nuculana attenuata, Flem. 



Batostomella sp. Bellerophon Urei, Flem. 



Bhabdomesonrliombiferum^hiM. B. decussatus, Flem. 



Athyris ambigua, Sow. Loxonema sp. 



Orthis resupinata, Mart. Macrochilina sp. (imbricata?) , Sow . 



Productus semireticulatus, Mart., Pleurotomaria sp. 



var. Orthoceras sp. 

 Productus, several species indet. 



About this assemblage of fossils there is something that is here 

 peculiar. Suppose I were requested to collect such a suite from the 

 stratified, rocks of North-Eastern Fife I should certainly not go to any 

 portion of the Calciferous Sandstones (the strata through "which the 

 agglomerate can be seen to rise), but to some of the well-marked 

 marine horizons in the lower portion (Lower Limestones) of the next 

 overlying group of sediments, the Carboniferous Limestones. It 

 would, of course, be natural to expect that the fragments which 

 furnished the foregoing list of fossils must have been derived from 

 some calcareous stratum underlying this precise portion of the coast- 

 line anterior to the volcanic outburst. As has been said, however, 

 the only known limestone at this part is the Encrinite-bed, but from 

 that horizon the following species have not so far been obtained — 

 Lithostrotion irregulare, Zaplirentis, and Orthis resupinata. In addition 

 to this the mode of occurrence of the corals is quite different from 

 that in the Encrinite-bed. Blocks are found entirely made up of the 

 cylindrical corallites ef Lithostrotion, and are just such as we should 

 expect to have been derived from some of the Lower Limestones. 

 Again, the size of the blocks renders an Encrinite-bed parentage 

 improbable ; one at the upper part of the beach was found to measure 

 20 X 14 x 12 inches, and the Encrinite-bed in the near vicinity is only 

 some 5 inches thick. 



Having therefore established the fact that these limestone fragments 

 belong to a higher stratigraphical horizon than any through which 

 the vent can now be seen to rise, how can their presence here be 

 accounted for? The most probable explanation appears to be that 

 some at least of the Lower Limestones formerly overspread this 

 portion of the county, and were actually penetrated by the vent. 

 The disrupted fragments were enclosed in the agglomerate which 

 subsequently subsided within the orifice, while the overlying and 

 surrounding sedimentary rocks have been entirely swept away. 



III. — On some British Pillow-lavas and the Bocks associated 



WITH THEM. 



By Henry Dewey and John Smith Flett. 



(By permission of the Director of H.M. Geological Survey.) 



rpHE pillow-lavas are a group of basic igneous rocks that occur, in 



JL our experience, only as submarine flows, and very frequently 



exhibit ' pillow-structure '. A lava-flow of this type is composed of 



