326 
Dr, H. H, Hess, Princeton University, has analyzed "black 
sand" leached out of limestone which was obtained in cores from south of 
Bermuda. Ina letter to the laboratory Dr, Hess describes it as '' Perov- 
skite, Fi-garnet (melanite), black magnetic opaque material probably 
titaniferous magnetite and nearly opaque rounded grains of deep red brown 
color which probably are rutile," 
From the 200 fms, (366 m,) seamount east of the Atlantis Sea- 
mount (34°08! Ny, 30° 14! W) there was dredged about half a ton of flat 
calcareous rocks composed primarily of foraminifera, pteropods and 
bryozoa, The rocks are quite well cemented and appear on underwater 
photographs to be eroded, rounded fragments of the formation which un- 
doubtedly underlies the truncated top of the mount, At present the temper- 
ature at the surface in this area is about 22°C and the temperature near 
200 fathoms is about 12° C, 
Dr, C. Emiliani, the University of Chicago, has made paleotem- 
perature determinations by the oxygen isotope method on a sample of 
these rocks, The benthonic foraminifera gave a temperature of 16, 840.5°C, 
A radiocarbon «cy age determination was made on a sample of 
the rocks by Dr. J, L. Kulp, Lamont Geological Observatory. It was 
found to be 12, 000+900 years, 
The age of the rock, 12,0004900 years according to Kulp, agrees 
reasonably well with that of the Two Creeks or Allergd phase, which 
Libby! found to have an average age of 11,400+4350 years, At that time 
1, Willard F, Libby, Radiocarbon Dating, U. of Chicago Press, 1952, 
Pe 88, 2 
