150 
the same order of superposition in the basins of the Forth and the 
Tay, including the submarine forest of the latter, will be found to 
be of the same age, though nothing at present is known of their 
fossils, except the discovery in the elevated beds of the Tay of the 
Nucula Corbuloides by Mr. Lyell; and that the parallel roads of 
Glenroy, recently shown by Mr. Darwin to be of marine origin, may 
be of cotemporaneous formation. Mr. Smith is also convinced, that 
avery great proportion of the superficial beds of sand, gravel, and clay 
are tertiary, although the evidence must sometimes be uncertain, 
owing to the want of organic remains. 
During the post-tertiary period, Mr. Smith is of opinion, an ele- 
vating movement to the extent of 40 feet took place, and that at this 
height, the relative level of sea and land remained stationary for a con- 
siderable time, exceeding the present period of repose. The proof 
of this, he states, is a magnificent range of inland sea cliffs, with beds 
of gravel and sand interposed between them and the sea*. At first 
Mr. Smith supposed that the beds of this period contained a small 
proportion of unknown species ; latterly, however, he reduced the 
number to one, the Arca papillosa, which has within a few weeks 
been discovered recent by Capt. Portlock on the coast of Ireland. 
During the existing geological epoch no change of level appears to 
have taken place in the Basin of the Clydet. 
To the paper is appended a list of the shells found in these beds, 
but not known as inhabitants of the British seas, and of which the 
following is a summary. 
Fossil in the Basin of the Clyde. Fossil in other localities. Reeent in the 
Melina VORA .222..\...c00) onccasancesececeascnasaecoore Arctic Seas. 
Crassina multicostata ...... Norway and Sweden. 
NWatham yer. cer. Wirk and Bridlington... Rothsay Bay. 
oxealicn ce acces. Dalmuir ......... Sacpacnac Arctic Seas. 
Mya truncata, var.? ...... Uddevalla; Canada ... St. Lawrence. 
Pecten Islandicus ......... sessepaseccsors nurOnB-CAMGADD Noun peas ei of 
Nucula oblonga. ee ae 
antiqua. 
corbuloides ...... Dundee; crag of Norwich. 
Mactra striata. 
Saxicava sulcata. 
Panopeea Bivonee........+00 Crasritsrcilyaceveasss se: Yorkshire coast. 
Natica clausa ...... paptoaose Wddevallay Mee cee esc B90 Ra 2 at Boe me 
glaucinoides. ibis sai 
TiREISTI VIS Gucmaoasaneseine Crag. 
Nassa Monensis ............ Isle of Man. 
Buccinum granulatum ... Crag. 
striatum. 
Trochus inflatus. 
PDTIR BOMEX PANTS lence esa asolleascesass sececcesecesecescsese Arctic Seas. 
: North Seas; coast of 
Melupinaiundatasncales verse! assests necchosao64 decals 5d00 None eaie a 
Fusus Peruvianus ......... Crag....ccccrscsresereveceees Arctic Seas. 
imbricatus. 
Bulbus Smithii. 
* Proceedings, vol. ii. pe 428. } Lbid., vol. ii. ps 428, 
