iy CONTKNTS. 



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 



VIU. Description of Lerneonema Bairdii. By Dr. James Salter. 

 (With a Plate.) ^^ 



IX. Observations on Furcellaria fastigiata, Huds., and Polijides 

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



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

 Clark, Esq ^^ 



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



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



M. Leon DuFOUR ^'2 



XIII. DeBcripiions oi Aphides. By Francis Walker, F.L.S. ... 118 



New Boohs : — 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 oi 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 Malacobdellce, 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 i\\Q gewus Hahrothamnus. By Joun Miers, Esq., F.Il.S., 

 F.L.S 180 



