igo2. 



HiNCH. — Glacial Geology of Co, Dublm, 



235 



present. Mr. Lamplugh very kindly informed me of the 

 existence of this section, which on examination yielded the 

 following species : — 



LAMEIvIylBRANCHIATA : 



Pecten opercularis, Linn. (?) Astarte borealis, Chein. 



Gardium, sp. A. compressa, Mont. 



Cyprina islandica, Linn. A. sulcata, Da Costa. 



Gastropoda : 



DentaHum entaUs, Linn. 

 Littorina sp. 

 Turritella terebra, Linn. 



Trophon Bamffius, Donovan. 

 Nassa incrassata, I\Filley. 



The position in which the shells in all these sections were 

 found is of considerable interest, for in no case was there any 

 indication that the shells lived in the beds in which they now 

 occur. In fact, the evidence pointed the other w^ay, all the 

 valves of the Lamellibranchs being separated and scattered 

 up and down the sections in a most indiscriminate manner. 

 In none of the localities examined was there anything of the 

 nature of a beach seen. 



The following is a list of localities m the South Dublin 

 district from which shells have been collected, giving heights 

 above sea level, the number of species obtained ; doubtful 

 species being excluded, and the number of exotic forms found 

 in each locality specified : — 



