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organism as " Cryptozoon " would be, is not probable. Perhaps the structure 

 is the shell of some specialized organism included in the concretion. Until 

 someone can find organic structures in "Cryptozoon" the description of 

 new species is an unnecessary burden to science. 



c. w. w. 



On the Radioactive Matter in the Earth and the Atmosphere. By 

 A. S. Eve. Separate from the Philosophical Magazine, Septem- 

 ber, 1906, pp. 189-200. 

 For geologists, the most important feature of this paper is the determina- 

 tion of the radioactive matter in the earth's crust. "About i . 8 X lo"^^ grams 

 of radium bromide is the estimated equivalent of the active matter per c.c. 

 present in the earth's crust sufficient to account for the penetrating radia- 

 tion." This is four times the average amount found by Strutt by direct 

 observation on rock specimens, 



c. w. w. 



