CONTENTS. 



Page 

 Art. XXVI. — Description of a new Species of Aruchnides, of 



the Genus Epeira, of M. Wulckenaer. By C.Vauthier 224 



Art. XXVII. — On a Quadruped belonging to the Order 



Rodentia. By Thomas Say 227 



Art. XXVIII. — Note on the supposed Identity of the genus 



Isodon of Say, with Capromys. By Thomas Bell, 



Esq. F.L.S 230 



Art. XXIX. — Memoir upon a new genus of Fossil Poly- 



paria. By M. Le Saw age 231 



Art. XXX. — Memoir on an American Bat, a New Species 



belonging to the genus Nyctinomus. By M. Isidore 



Geoffroy Saint-IIilaire 233 



Art. XXXI. — A Revision of the Family Equidos. By Mr. 



John Edward Gray, M.G.S 241 



Art. XXXII. — Descriptions of three new Species of Leth- 



rus. By Professor Fischer 249 



Art. XXXIII. — A Description of Two new species of Heli- 



cinac, and Explanation of the Figures to the Monograph. 



By Mr. John Edward Gra r, M.G.S. 250 



Aut. XXXIV. — Description of a remarkable Fossil, found 



in Coal Shale : with Observations. By J. D. C. 



Sowerby, Esq. F.L.S. 252 



Art. XXXV. — On the Structure of Melania Setosa. By 



Mr. John Edward Gray, M.G.S 253 



Art. XXXVI. — Abstract of a Monograph on a new Genus 



of Gasteropodous Mollusca, named Scissurella ; by M. 



Alcide Dessalines D'Orbigny. With Notes by 



G.B. Sowerby, F.L.S 255 



Art. XXXVII. — Mulleria, a new Genus of Fresh-water 



Bivalves, of the Family of Ostreacea?, established by 



M. Le Baron D^Audemard de Ferussac 258 



Art. XXXVIII. — Analytical Notices of Books : — 



Monographia Tenthredinetarum 259 



Annates des Sciences Naturelles 264 



Curtis' s British Entomology 265 



Sowerby's Genera of Recent and Fossil Shells 266 



