APPENDIX. 



Appendix II. 



M. G. Dollfus, in reading over the proofs, has reminded us 

 that the Sands of the Soissonnais have been divided by M. 

 Watelet into three horizons as follows : — 



Upper : Sands of Visigneux. 



Middle : Sands of Cuise. 



Lower : Sands of Aizy. 

 The upper horizon is typically developed at Visigneux, about four 

 miles south of Soissons, and is particularly characterised by the 

 abundance of Turritella ; it has a wide extension, and is again met 

 with in Flanders. 



