Revue Politique; London Kature; the Royal Geographical 

 Society ; the Nova Scotian Institute ; the Boston N. H. Society ; 

 Cambridge Museum ; Prof. O. C. Marsh ; the Connecticut 

 Academy; Commissioners of Fisheries of New Jersey; Penn 

 Monthly ; Medical News ; Mr. Geo. W. Childs ; the U. S, 

 Chief of Engineers ; Librarian of Congress ; and Wisconsin 

 Historical Society. 



The death of Prof. Carl Naumann, at Leipsig, on the 26tli 

 November, 1873, was announced. 



Prof. Cope stated that the species figured and described 

 by Prof. 0. C. Marsh, in a paper received for the Library 

 to-night, under the name of Brontotheriwn ingens, is the 

 • one described by himself under the name of Symhorodon 

 'i.rigonoceras, in the Synopsis of Extinct Vertebrata of Colo- 

 . rado, issued in October, 1873, by the U. S. Geological Survey 

 of the Territories. 



P]'ofessor Frazer said : " A few meetings ago I referred to 

 the fact that the white color ot the moon by day was due 

 to the fact that the dispersed blue light of the sun just 

 supplied the dispersed blue light of the mioon, and I suggested 

 that the solar origin of these otherwise missing rays might 

 he demonstrated by choosing the first or third quartering of 

 the moon (when lines joining the sun and earth, and the 

 earth and moon, meet nearly at right angles), and regarding 

 the moon through the Nicols prism. As under these circum- 

 stances the solar light would be polarized, a change between 

 white and yellow ought to be perceived. The experiment 

 bore out this hypothesis, although, owing to the perfect 

 reflection from suspended particles of greater size than those 

 which reflect the blue light, the color was not a perfect 

 yellow." 



Professor Lesley exhibited a recently executed large manu- 

 script map of a hundred square miles of the surface of Centre, 

 Huntingdon, and Blair Counties, in Middle Pennsylvania, 

 with three vertical sections crossing the district — one along 

 the Little Juniata River ; another two miles further east, 

 along Warrior Run ; and a third five miles further east, 



