124 The Ottawa Naturalist. 



other geological subjects ; being the result of personal work 

 in both JiemispJieres from 184.5 to i8g§. 



Trans. Roy. Soc. Can. (Presidential address.) Extract from 

 Volume II second series, 1896-97. Ottawa, 1896. 



Miller, W. G. and Brock, R. W. — " 8ome dykes cutting the 

 Laiirentian series in the counties of Frontenac, Leeds 

 and Lanark, Out." Can. Rec. Sc, 8 pp., 3 plate, October, 

 Montreal, 1895. 



Miller, W. G. — " Minerals and the Roentgen Rays." Amer. 

 Geol. Vol XVII, No. 5, pp. 324-325, Minneapolis, May, 

 1896. 



Thin sections of granite, hornblende gabbro, quartz, beryl, 

 garnet corundum and diamond, together with a small grain of 

 glass were subjected to the X rays and it was found that carbon 

 and its compound arc "more transparent than inorganic sub- 

 stances " Crystals of hydrated compounds appear to be 

 generally less opaque than those ot the corresponding anhydrous 

 materials. Experiments on relative transparency of a number 

 of liuqids were also made and these prove very great. H2 SO4 

 was found to be the most opaque of any examined by Dr. 

 Miller. An excellent figure accompanies the paper. 



WiMAN, Carl — "Ueber die Gixqjtoliten." Bull. Geol. Inst. Upsala 

 No. 4., Vol. II, Pt. 2, 74 pp. plates 9-15, 1895. 



Claypole, E. W. — " The ancestry of the Upper Devonian, 

 Placodernis'of Ohio." Amer. Geol. XVII, No. 6 pp. 349- 

 360, Minneapolis, June, 1896. 



Sapper, Carlos D. — " Sobre la geografia Fiscia y la geologia 

 de la Peninsula de Yucatan." Instituto Geol. Mexico, 1896. 



This treatise deals with the geology orography and 

 hydrography of the peninsula of Yucatan to which is appended 



