IV CONTENTS. 



NUMBER XXXII, 



Page 



VII. Chronological Exposition of the Periods of Vegetation and the 

 different Floras which have successively occupied the surface of the 

 Earth. By M. Adolphe Brongniart 73 



VIII. DescriTption of Lerneone7na Bairdii. By Dr. James Salter. 

 (With a Plate.) 85 



IX. Observations on Ftircellaria fast'igiata, Huds., and Polyides 

 rotundus, Gmel. By Dr. Robert Caspary. (With three Plates.) ... 87 



X. Observations on the Animals of the Bullidce. By William 

 Clark, Esq 98 



XI. Notes on Crustacea. By C. Spence Bate. (With a Plate.)... 109 



XTI. On the different modes of Aquatic Respiration in Insects. By 

 M. LjfeoN DUFOUR 112 



XIII. Descriptions of y/p/ijrfes. By Francis Walker, F.L.S. ... 118 



New Books : — The Tourist's Flora : a descriptive Catalogue of the 

 Flowering Plants and Ferns of the British Islands, France, Ger- 

 many, Switzerland, Italy, and the Italian Islands, by Joseph 

 Woods, F.A.S., F.L.S., F.G.S.— Zoology for Schools, by Robert 

 Patterson 122—124 



Proceedings of the Royal Society ; Zoological Society ; Botanical So- 

 ciety of Edinburgh 125 — 143 



The Velvet-like Periostraca of Trigona, by J. E. Gray, Esq. ; Mon- 

 strous Flowers of Pelargoniums ; The Transformation of Mollusca, 

 by J. E. Gray, Esq. ; Notice of the occurrence of Eleocharis uni- 

 glumis, Link, near Blackness Castle, Linlithgowshire, by John 

 T. Syme, Esq, ; On the Names of the Victoria Water Lily, by J. 

 E. Gray, Esq, ; On the Organization of the Malacobdellee, by M. 

 Emile Blanchard ; Monograph of the recent species of Trigonia, 

 including the description of a new species from the Collection of 

 H. Cuming, Esq., by Arthur Adams, R.N., F.L.S. &c. ; Obituary 

 — The Rev. William Kirby; Meteorological Observations and 

 Table 143—152 



NUMBER XXXIII. 



XIV. The Natural Relations between Animals and the Elements in 

 which they live. By L. Agassiz 153 



XV. On the genus Hahroihamnus. By John Miers, Esq., F.R.S., 

 F.L.S 180 



