CONTENTS. 



Page 



Art. XXI. — Velocity of the Propagation of Magnetism ; by 



II. A. Perkins „ _. _ 165 



XXII. — Geomorphic Origin and Development of the Raised 

 Shore Lines of the St. Lawrence Valley and Great 

 Lakes ; by R. Chalmers, LL.D., of the Geological Sur- 

 vey of Canada 175 



XXIII. — Material and Shape of the Rotating Cathode ; by 



H. E. Medway _ _ _ _ _ 180 



XXIV. — Structure of the Upper Cretaceous Turtles of New 

 Jersey : Lytoloma ; by G. R Wi eland. (With Plates 

 V-VIII) 183 



XXV. — The root-structure of North American terrestrial 



Orchidese ; by.T. Holm. (With figures in the text) 197 



XXVI. — Study of the Structure of Paleozoic Cockroaches, 

 with Descriptions of New Forms from the Coal Measures; 

 by E. H. Sellards _. 213 



XXVII. — Electrotropism of Roots ; by A. B. Plowman. 



(With Plates IX and X) 228 



SCIENTIFIC INTELLIGENCE. 



Geology and Mineralogy — United States Geological Survey, 237. — Geologi- 

 cal Survey of Canada : Examination of the Coral-Rock Cores from the 

 Borings at Funafuti, J. W. Judd and C. G. Cullis, 239. — Brief notices 

 of some recently described Minerals, 242.— New York State Museum, 243. 

 Observations of a Naturalist in the Pacific, H. B. Guppy, 244. 



Miscellaneous Scientific Intelligence — Elements of Algebra for Beginners, G. 

 W. Hull : Elementary Algebra, J. H. Tanner, 244. 



, 



