386 



NOTES ON GEOLOGICAL RESULTS. 



mound . . . above this diluvial clay affords a solution of 

 the problem and points clearly to whence the line was derived." 



If Mr. Sinel is correct the concretions will occur 

 wherever there is a source of lime. I see no objection to this 

 view in theory, but I have found that the lime in the inland 

 clay has not, as far as at present observed, had the effect. 

 Evidently, as far as Guernsey and J ersey are concerned, the 

 concretions occur on the sea coasts only, although there is 

 lime in other clays. 



Geikie describes Loss a " somewhat calcareous and 

 sandy clay .... accumulated by the drifting action 

 of the wind."* " Very often contains concretions."! 



" The Loss is probably a subaerial deposit formed by 

 long-continued drifting of fine dust by the wind."t 



This description does not adapt itself to our layer in 

 which the concretions are found. 



Lyell§ writes : " In Germany the accumulation of Loss 

 has taken place on an enormous scale .... although 

 for the most part unstratified, it betrays in some places marks 

 of stratification, especially where it contains calcareous con- 

 cretions. || 



This description fits our deposit and in contra-distinction 

 to Geikie ; Lyell describes it as " fluviatile " and looks upon 

 it as a river deposit, not as wind blown. 



The Shells found in the Guernsey Concretions and 

 named are : — 



1. Helix aspersa (land species) 



2. „ virgate ... „ 



3. „ hispida ... „ 



4. Pupa umbilicata „ 



5. „ muscorum (marginate) „ 



6. Succinea elegans (marsh species) 



These shells have been found in the corresponding 



English deposit. They are also present in the Continental 

 deposits.1T Lyell figures 1 and 5, Prestwich gives a list of 

 13, of which the above 6 form a part, as being found in the 

 same deposit. 



If we may call these shells fossils then they are the first 

 fossils found in the island. 



The deposits have been visited by Mr. E. D. Marquand, 

 Mr. Sinel and myself, four times this summer, and the naming 

 of the shells was undertaken by Mr. Marquand. 



* Class book of Geology, Archibald Geikie, L.L.D., P.R.S., fol. 202. 



X Also fol. 472. t Also Prehistoric Europe, fol, 144. 



§ Student's Elements of Geology, 1878. Sir Charles Lyell, fol. 413. 

 || The italics are mine.— A. C. 1 See Lyell's " Student's Elements," fol. 134. 



