CONTENTS TO VOLUME XVL 



NunilDer 91. 



Page 

 Art. I. — Observations on the Genus Romingeria ; by C. E. 



Beecher. (With Plates I-V) 1 



II. — Comparative Study of Some Isomorphous Triple Thio- 



cyanates ; by J. C. Blake .._. 12 



III. — Studies in the Cyperacese ; by T. Holm 17 



IV. — Cbrysocolla : A Remarkable Case of Hydration; by 



C. M. Palmer 45 



V. — Inquiry into the Cause of the Nebulosity around Nova 



Persei ; by F. W. Very . ! 49 



VI. — Heat of a Change in Connection with Changes in Die- 

 lectric Constants and in Volumes ; by C. L. Speyers.. 61 



VII. — Notes on the Genus Baptanodon, with a Description 



of a New Species ; by W. C. Knight 76 



VIII.— Characters of Pteranodon ; by G. F. Eaton. (With 



Plates VI and VII) 83 



IX. — Codonotheca, a New Type of Spore-Bearing Organ 

 from the Coal Measures; by E. H. Sellards. (With 

 Plate VIII) - .._ 87 



X. — Note on the Dates of Publication of Certain Genera of 



Fossil Vertebrates ; by L. P. Bush 96 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Spinthariscope, W. Crookes : Properties of Sodium 

 Sulphate Sohitions, Marie and Marquis : Eadio-active Lead, Hofmann 

 and WoLFL, 99. — Colloidal Silver, Hanriot : Iodides of Caesium. H. W. 

 FooTE : Quantitative Chemical Analysis by Electrolysis, A. Classen, loO. 

 — Chemisches Praktikum, A. Wolprum, 101. 



Geology and Natural History — United States Geological Survey, 101. — New 

 York State Museum, F. J. H. Merrill, 102. — Geological Survey of New- 

 Jersey, 103. — Maryland Geological Survey : Geography and Geology of 

 Minnesota, C. W. Hall, 104. — Plumasite, an oligoclase-corundum rock 

 near Spanish Peak, Cal., A. C. Lawson : Experimental Garden in Cuba, 

 E. F. Atkins, 105. 



Miscellaneous Scientific Intelligence — United States Coast and Geodetic Sur- 

 vey, 0. H. TiTTMAN : National Bureau of Standards, S. W. Stratton: 

 Scientific Writings of George Francis Fitzgerald, J. Larmor, 106. 



Obituary — J. Peter Lesley, 106. 



