Royal Society, 55 



to show that the animals under consideration are united by many pe- 

 culiarities, these serving to distinguish them from all other quadru- 

 peds ; whilst the rich collections now in the British Museum, and in 

 that of the Zoological Society, show that the most dissimilar forms 

 of marsupial animals are linked together by species exhibiting the 

 intermediate grades of structure." 



Mr. Waterhouse next enters into an examination, brief but still 

 satisfactory, of their structural peculiarities, in which he refers to 

 the labours of Professor Owen and others who have thrown so much 

 light upon them. With respect to the mode in which the species 

 are worked out, we cannot speak too highly. In the instances (and 

 they are not few) where a confusion of synonyms has perplexed the 

 inquirer, we find the knot unravelled ; and though, in many cases, 

 names given by modern naturalists to old and previously described 

 species must sink, we feel assured that the imposers themselves of 

 these names will rejoice, so that science be but benefited. The de- 

 scriptions are full and clear ; nearly all of them, indeed, says the 

 author, were " carefully drawn up by myself from the original speci- 

 mens contained either in the museum at Paris, the British Museum, 

 or that of the Zoological Society*." 



We cannot conclude our notice of the present really valuable con- 

 tribution to natural history without referring to the plates. These, 

 to the number of thirty-four, are faithful delineations of the species 

 represented, and are at once effective and artistical. 



PROCEEDINGS OF LEARNED SOCIETIES. 



ROYAL SOCIETY. 



May 20, 1841. — The following papers were read, viz. — 



1. "Catalogue of Geological Specimens procured from Kergue- 

 len's Land during the months of May, June, and July, 1840." 



2. " Catalogue of Birds collected on board Her Majesty's Ship 

 Terror, between the Cape of Good Hope and Van Diemen's Land." 



3. " Description of Plants from Kerguelen's Land, collected in 

 May, June, and July, 1840." 



The above papers are by John Robertson, Esq., Surgeon of Her 

 Majesty's Ship Terror, and were presented to the Society by the 

 Lords Commissioners of the Admiralty, and communicated by the 

 President of the Royal Society. 



4. "On the Fossil Remains of Turtles discovered in the Chalk 

 Formation of the South-East of England." By Gideon Algernon 

 Mantell, Esq., LL.D., F.R.S. 



In this paper, the author gives a description, accompanied with 

 drawings of a remarkable fossil Turtle, referable to the genus Emys, 

 and named from its discoverer, Mr. Bensted, the Emys Benstedi, 

 which has been lately found in a quarry of the lower chalk of Kent, 



* And here it may be observed, that the number of species at present 

 known, all of which are described in the volume before us, amounts to ninety- 

 seven. Desmarest, in his < Mammalogie' ( 1 820), has characterized only forty- 

 three. 



