86 SIXTH REPORT — 1S3G. 



crag. The bones, principally belonging to the phalanges, have not yet 

 been minutely compared with the corresponding portions of skeletons 

 of existing species. These remains occur at Southwold, and have un- 

 dergone the same chemical change as the bones of mammalia. 



No remains which can be satisfactorily referred to the reptilia have 

 been discovered in the crag. 



The remains of fish are very abundantly dispersed throughout the 

 red and mammiferous crag, but are less plentiful in the coralline. Oc- 

 curring only as detached bones, it is not very easy to arrive at any very 

 satisfactory results in their examination. Their distribution throughout 

 the three deposits is as follows : — 



Mammiferous Crag. — Bones of the genus Platax in immense nunjbers ; 

 several species of the genus Raia, vertebrae of genera totally new to 

 Agassiz. 



Red Crag. — Teeth of Carcharias, several species, including C. Megalo- 

 don of Agassiz ; palates of Myliobatis ; teeth of Lamna, Notidanus, 

 Galeus. 



Coralline Crag. — Genera undetermined. 



On the Fallacies involved in Mr. LyelTs Classification of Tertiary Deposits 

 according to the proportionate number of recent Species of MoUusca 

 which they contain. By E. Charleswoeth, F.G.S. (The abstract 

 of this communication has appeared in Jameson's Edinburgh Phil. 



: Journal ; and the author has subsequently treated of the subject in 

 the Phil. Mag. and Annals for January, 1837, and also in the new 

 Series of Loudon's Magazine of Natural History. 



On certain Limestones and associated Strata in the Vicinity of Manchester. 

 By Professor Phillips, F.R.S., SfC. 



The subjects treated of in this Memoir were those members of the 

 saliferous and carboniferous formations near Manchester which offered 

 circumstances of interest in the general study of these deposits, or spe- 

 cially important as bearing on a general conclusion presented by the 

 author, that betn-een Manchester and Shrewsbury a great deposit of 

 coal probably exists below the new red sandstone rocks, though, from 

 its want of conformity to these rocks, and the great depth at which only 

 it could be found, the search for it might be at this moment unadvisable. 



Referring to the pre^nous notices of thin limestones associated with 

 coloured marls and inclosed between rocks of red sandstone at Colly- 

 hurst near Manchester, the author proved by sections and analysis of 

 specimens, and accounts of organic remains, that these certainly be- 

 longed to the magnesian limestone formation. On the contrary, the 

 limestone of Ardwick, near Manchester, was proved to belong to the 

 upper part of the coal formation, and to contain, in its position with 

 reference to the coal, its fossil remains, mineral composition, and asso- 

 ciated deposits, perfect evidence of identity with the limestone of the 

 Shrewsbury coal-field, first noticed by Mr. IMurchison. 



