248 ' Geological Society. 



Fig. 4. Cidaria albipunctaria, sp. n., $ , p. 642. 

 Fig. 5. Larentia nitidaria, sp. n., <$ , p. 657. 

 Fig. 6. Hydrelia distinctaria, sp. n., tf, p. 80- 

 Fig. 7. Larentia grataria, Leech, cJ,p. 6-56. 

 Jty. 8. Larentia (?) intersectaria, sp. n., tf, p.^667. 

 jP^. 9. Photoscotosia fasciaria, sp. n., <, p. 672. 

 Fig. 10. Cidaria fervidaria, sp. n., <, p. 646. 

 .Ft*/. 11. Larentia tripunctaria, sp. n., <$ , p. 666. 

 Fig. 12. Hydrelia electaria, sp. n., J, p. 81. 

 Fig. 13, Cidaria postalbaria, sp. n., rf, P- 64*5. 

 Fig. 14. Larentia costinotaria, sp. n., <? , p. 670. 

 Fig. 15. Cidaria ochracearia, sp. n., cf > P- 643. 



Fig. 16. fulgidaria, sp. n., cf, p. 641. 



/*p. 17. etifochraria, sp. n., (J, p. 647. 



Fig. 18. Hydrelia angularia, sp. n., (J, p. 82. 



PROCEEDINGS OF LEARNED SOCIETIES. 

 GEOLOGICAL SOCIETY. 



May 12, 1897. Dr. Henry Hicks, F.R.S., 

 President, in the Chair. 



The following communication was read : 



< The Mollusca of the Chalk Rock : Part II.' By Henry 

 Woods, Esq., M.A., F.G.S. 



The first part of this paper, dealing with the Cephalopoda, 

 Gasteropoda, and Scaphopoda, appeared in the last volume of 

 the Quarterly Journal (vol. Hi. p. 68). In the present commu- 

 nication the Author gives an account of the characters, synonymy, 

 and distribution of the Lamellibranchia : 29 species are recognized, 

 6 being new ; the genera represented are : Leda, Nucula, Area, 

 Limopsis, Modiola, Inoceramus, Ostrea, Chlamys, Lima, Spondylus, 

 Plicatula, Cardium, Cardita, Arctica, Trapezium, Corbis'l, Martesia?, 

 and Cuspidaria. 



In the concluding part the Author compares the fauna of the 

 Reussianum-zone (Chalk Rock) in England with that of other 

 European areas, particularly N.W. Germany and Saxony. In the 

 latter country the number of species in some groups particularly 

 Gasteropoda and Lamellibranchia is much greater than in Eng- 

 land ; this difference is probably due to the sea having been of less 

 depth than in the English area. It is noticed that the species of 

 Cephalopoda have a much wider geographical distribution than the 

 other groups of the Mollusca. 



Finally, by a study of the present distribution of the genera 

 particularly of those which form the predominating element in the 

 fauna, taken in conjunction with the other characters of the 

 zone, the Author arrives at the conclusion that in England the 

 Reussianum-zone was probably formed between the depths of 100 

 and 500 fathoms. 



