424 Newer Pliocene and Post Pliocene Deposits 



miles above Quebec," on the south side of the St. Lawrence, at the 

 head of a rocky ravine, 400 yards from the river, and 180 feet 

 above its level." These shells belong to a level much higher than 

 that which has afforded the greater number of the species at Mon- 

 treal and Quebec. The assemblage is considerably different from 

 that at other localities, Tellina calcarea predominates, and is of 

 very large size, some specimens being 1^ inch in length. Balanus 

 Hameri is a very abundant, and sometimes has its opercular 

 valves, also Mya truncata, the latter of small size. The only other 

 shells are Saxicava rugosa, and Astarte Laurentiana, Trichotropis 

 borealis and Buccinum undatum. The matrix is stony clay. This 

 deposit though at a considerable elevation, was probably formed in 

 deep water. 



As I observe in a note in the Edinburgh New Philosophical 

 Journal for October, that Professor H. J. Rogers is still disposed 

 to consider the shells found at a height of 470 feet on the Mon- 

 treal Mountain, as having been " swept thither from a much 

 lower level," I presume by earthquake waves ; I think it neces- 

 sary to add to the statements above given, that the shells occur 

 only in stratified sand and fi^ne gravel, alternating in thin layers 

 precisely in the manner of a modern beach. The shells are of 

 course not precisely in situ, being arranged in layers among the 

 sand, but their arrangement indicates merely the ordinary action 

 of ,the waves on the shores of a bay. The error of Professor 

 Rogers may have been caused by his confounding the stratified 

 fossilferous sand with the unstratified debris which overlies it, and 

 which may perhaps indicate subsidence and ice drift subsequent 

 to the formation of this beach. I think it more probable, how- 

 ever, that this overlying confused mass has resulted from the 

 sobaerial waste of the steep slope above the beach. The existence 

 of this incoherent terrace of sand and shells perched on a steep 

 and exposed hill side, is one of the most convincing proofs that 

 could be desired that no cataclysmal waves have swept over the 

 Montreal Mountain since the sea stood at this level. It is proper 

 to add that Sir C. Lyell, writing in 1845,* clearly distinguishes 

 the stratified shell bearing beds from the unstratified mass above. 



A very interesting collection of recent shells from the mouth 

 of the St. Lawrence, has just been brought to Montreal by Mr. 

 Bell, a young gentleman employed on the Geological Survey. It 



* Travels in North America, vol. 2. 



