3 



the post-pleiocene, or raised-beach formations were accumulated. 

 The shells are generally entire, even delicate specimens being in 

 good preservation. 



The deposit may be studied in almost any deep cutting; and 

 shells occur in many localities. One of the richest lies along the south 

 shore of the Kyles of Bute, opposite the Burnt Isles. Here a stream 

 on the Bute side has cut into the deposit, and exposed the shells. 

 Mya udevallensis, a boring shell, is in its natural upright position ; 

 25 species were found. Another rich locality was a bed on the side 

 of the railway between Port-Glasgow and Greenock, 50 feet above 

 the sea level. The shells were in a series of thin beds of sand, gravel, 

 and clay, resting on the lower boulder Till of unknown thickness. 

 Here Mr. Smith found 33 species. Over the shell bed were, sand 10 

 feet ; coarse gravel 2 feet ; and vegetable soil. 



7. The following is a list of the shells of the boulder clay not found 

 in a recent state in the British seas, kindly supplied by Mr. Smith. 

 The entire number he estimates at 151 : 



Tellina proxima : Arctic seas. 

 Astarte multicostata. 



Propinqua. 



Withami : Bridlington : Arctic seas. 



Borealis : Upper Crag : Arctic seas. 



Mya udevallensis : Arctic seas. 



Pecten islandicus. 

 Leda oblonga. 



antiqua. 



Cytherea laevagita. 

 Mactra striata. 

 Natica clausa. 



Smithii (Bulbus, Brown). 



fragilis. 



glaucinoides. 



Nassa Monensis. 

 Buccinum striatum. 



granulatum. 



Trochus inlatus (Margarita undulata, Sowerby ?) : Arctic seas. 



Littorina expansa : Arctic seas. 



Velutina undata : Arctic seas. 



Fusus peruvianus : (Murex, Sowerby) : Crag, Udevalla ; Arctic 



seas. 

 Fusus imbricatus : Arctic seas. 



curtus. 



Saxicava sulcata, Udevalla. 

 Balanus udevallensis, Udevalla. 



8. These are not the only remains, however, yielded by the beds in 

 question. Those of mammalia now extinct in these islands have also 

 been found. Mr. Bald found an elephant's tusk in the excavation of 

 the Union Canal, 28 miles from Glasgow, in the west park of the 



