Vol. 58.] THE WOLLASTONITE-SCAPOLITE GNEISSES OF CEYLON. 689 
are never sheared or distorted, while the interlocking of the minerals 
at their junction with the matrix and their actual mineral com- 
position, manifest their contemporaneous character and close con- 
nection with other rocks of the Galle Group. 
EXPLANATION OF PLATE XXXIV. 
Geological sketch-map of Galle Fort and neighbourhood, on the scale of 
6 inches to the mile, showing the localities where wollastonite-scapolite 
gneisses are exposed. 
Discussion, 
Prof. Groom asked whether it was not possible that some of the 
splendid gneisses described by the Author had been formed by the 
intrusion of the more acid materials, along planes of foliation of 
a schist produced by the shearing of a solid rock. 
The Aurnor thanked the Fellows for the kind way in which they 
had received his paper. In reply to Prof. Groom, he said that he 
thought the mineral-banding of the Galle rocks was a true fluxion- 
foliation. There was no evidence of foliation in the basic portions 
of the rocks, previous to the introduction of the more acid portions. 
Basic lenticles included in more acid rock were common in the 
Charnockite Series, and there were transitions from these through 
pinched bands to ordinary mineral-banding. Simple mineral-banding 
was chiefly conspicuous at Galle, and this seemed to point to the 
squeezing of a ‘schlierig’ rock in the course of consolidation, during 
which there was perhaps a successive introduction of basic and acid 
types, the final residuum forming segregation-veins. 
Q.J.G.8. No. 232. 3B 
