P/- 



CONTENTS. 



Page 

 I. A New Fossil Crab from the Miocene Greensand Bed of Gay 



Head, Martha's Vineyard, with Remarks on the Phylogeny of 



the Genus Cancer. By Alpheus S. Packard 1 



II. On the Thermal Diffusivities of Different Kinds of Marble. By 



B. O. Peirce and R. W. Willson 11 



III. Geometry on Ruled Quartic Surfaces. By Frank B. Williams 17 



IV. On Supposed Merostomatous and Other Paleozoic Arthropod Trails, 



with Notes on those of Limulus. By Alpheus S. Packard . 61 



V. Certain Derivatives of Metadibromdinitrobenzol. By C. Loring 



Jackson and W. P. Cohoe 73 



VI. On the Continuity of Groups generated by Infinitesimal Transfor- 

 mations. By Stephen Elmer Slocum 83 



VII. On Hardystonite and a Zinc Schefferite from Franklin Furnace, 

 N. J. By John E. Wolff. With a Note on the Optical 

 Constants of the Schefferite. By Dr. G. Melczer . . . Ill 



VIII. On the Thermal and Electrical Conductivity of Soft Iron. By 



Edwin H. Hall 119 



IX. A New Conception of Thermal Pressure and a Theory of Solutions. 



By Gilbert Newton Lewis 143 



X. International Atomic Weights. By Theodore William 



Richards 169 



XI. Peripheral Distribution of the Cranial Nerves of Spelerpes bilin- 



eatus. By Mary A. Bowers 177 



XII. On Certain Derivatives of Orthobenzoquinone. By C. Loring 



Jackson and Waldemar Koch 195 



XII r. On the Action of Sodic Sulphite on Tribromdinitrohenzol and Tri- 

 bromtrinitrobenzol. By C. Loring Jackson and Richard 

 B. Earle 229 



