130 Free Remarks on the Geological Work 



Work, and further, that it should have been marked by italics! ; 

 and in order to show my readiness, to the giving of every degree 

 of publicity to what Dr. Lister did, with regard to Fossil Shells, 

 I have been at the pains to make out, as I hope, with tolerable 

 certainty, what are the Situations of all the Places, in modern 

 Maps, to which Dr. Lister refers in this work; and by means of 

 Smith's Map, joined with mv own knowledge of the local situa- 

 tions and extents of the several Strata, to assign each Shell its 

 place, in a Stratigraphical System : to which, I have added re- 

 ferences to Mr. Sowerbv's Mineral Conchology, wherever he ap- 

 pears to have described the same species of Fossil Shelly and I 

 now send you the same, and shall be glad to see it inserted, fol- 

 lowing this, in your Philosophical Magazine. 



Mr. Greenough's next passage, in page 28.), is as follows, viz. 

 " Mr. Strange traced the Gryphus from the lower part of ]\Ion- 

 mouthshire and Purton Passage, through Gloucestershire, Wor- 

 cesterhire, Warwickshire, and Leicestershire, occupying in these 

 counties, as in Northamptonshire, the lower parts under the hills," 

 and by a Note on this passage, he refers to the " Archseologia,'* 

 vol. vi. p. 36. I have from the volume last mentioned, carefully 

 extracted all which Mr. Strange says, on the subject ofOrganic 

 Remains, and have sent the same herewith, in hopes that it may 

 be recorded in your Work, following my abstract of Mr. Lister's 

 Work, above mentioned. Mr. Greenough, besides having intro- 

 duced here, the mention oi Nor thamptonshire,\\\\\c\\ Mr. Strange 

 does not mention (and wherein there is no part of the range of 

 the Lias Gryphites, Gryphaea incurva a, or G. obliquata, Min. 

 Conch, t. 112), he omits Mr. Strauge's mention of //i<? Gravel,\n 

 which he found some, and perhaps several of his Gryphites ; and, 

 almost without doubt, these Gravel Gryphites belonged to some 

 of the higher stratigraphical localities of this genus of Shells, 

 which are mentioned, P.M. liii. p. 124, or to others, and not to 

 the Lias Strata, whereon Mr. Strange's description sets out, in 

 Glamorgan and Monmouth Shires : and hence I think it fair to 

 conclude, that Mr. Strange, had not traced any Strata through 

 distant places, " by mere attention to their Fossils." 



Mr. Greenough's two following quotations, from the Journal de 

 Physique, seem .ittle to the purpose in question, because, appear- 

 ing to me merely having in view, the supposed relation between 

 mineral and ««f??ifl/ Species, as before mentioned. 



The Rev. A. Catcot, in page 161 of his " Treatise on the De- 

 luge," having spoken of thick and massive Rocks, subjoins a Note 

 which begins as follows, viz. A thick Rock or " single Stratum, is 

 <livided into a great number of lesser Strata or small Layers, which 

 will be easily distinguishable from each other, either by their co- 

 lour, depth, thickness, or more remarkably by their contents, or the 

 Fossil bodies they contain, one layer abounding with one species 



