Smithsonian Report, 1937.— Lane 



Plate 2 



• 



1, 2. MICROPHOTOGRAPHS OF THORIUM HALOS AFTER HENDERSONS LATEST 



PAPER. 



The outside riiiK has a radius of 0.0418 mm. (Proc. Uoy. Soc. London, voL 158, opp. p. 2(;8, pi. 9.) 



After I). E. Kerr-Lawson 



3. MICROPHOTOGRAPHS OF OVERLAPPING URANIUM HALOS. 



Compare the halos D. E. Kerr-Lawson published in rniversily of Toro nto Studies, Geological Series, Xo. 



24. pis. 2, 4, and Xo. 27, pis. 3. 4. 



