CONTENTS. V 



Page 

 New Books .■ — An latioduction to Conchology, or Elements of the 

 Natural History of Molluscous Animals, by George Johnston, 

 M.D., LL.D 217 



Proceedings of the Zoological Society ; Royal Institution 218 — 235 



Larus tridactylus ; Descriptions of new Entophyta growing within 

 Animals, by Joseph Leidy, M.D. ; On Fossil Rain Drops ; On the 

 Occurrence of Crystalline Bodies in Animal Tissues ; Meteorolo- 

 gical Observations and Table 235—240 



NUMBER XL. 



XXII. On the Geographical Distribution of the Bulimi, a genus of 

 terrestrial MoUusca, and on the modification of theu- Shell to the local 

 physical conditions in which the species occur. By Lovell Reeve, 

 F.L.S. &c. (With a Map.) 241 



XXIII. A Catalogue of British Spiders, including remarks on their 

 Structure, Functions, (Economy, and Systematic Arrangement. By 

 John Blackwall, F.L.S 256 



XXIV. Descriptions of new Land Shells from St. Helena, Ceylon, 

 and China. By W. H. Benson, Esq 262 



XXV. On the Composition of the Ash of Armeria maritima, grow- 

 ing in different localities, with remarks on the geographical distribution 

 of that Plant, and on the presence of Fluorine in Plants. By Dr. A. 

 VoELCKER, Professor of Chemistry in the Royal Agricultural College, 

 Cirencester 266 



XXVI. Notices of Australian Fish. By Sir John Richardson, 

 M.D., F.R.S 273 



XXVII. On the Chemnitzia opalina and C. diapkana. By William 

 Clark, Esq 292 



XXVIII. Notes on Crustacea. By C. Spence Bate. (With a 

 Plate.) 297 



XXIX. On Lastrea uliginosa, 'Nevim. By Thomas Moore, Esq., 

 F.L.S., Chelsea Botanic Garden 3q1 



XXX. Zoological Notes and Obsei-vations made on board H.M.S. 

 Rattlesnake during the years 1846-50. — On the Auditory Organs in 

 the Crustacea. By Thomas H. Huxley, Assistant Surgeon R.N. 

 (With a Plate.) 304 



XXXI. Contributions to the Palaeontology of Gloucestershire : — On 

 the Strombida of the Oolites. By Thomas Wright, M.D. With 

 the description of a new and remarkable P/eroceras. By John Ly- 

 cett, Esq. (With a Plate.) ^Of; 



