REPORTS AND PROCEEDINGS. 
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DUMFRIES AND GALLOWAY NATURAL HISTORY AND ANTIQUARIAN 
Society.—This Society had its first excursion for this season on 
7th June last, the district selected being that around Drumlanrig 
Castle. Shortly after nine in the morning members and _ their 
friends, to the number of about thirty-five, met at Dr. Grierson’s 
Museum at Thornhill. Having been conducted by Dr. Grierson 
over his well-arranged collection, which comprises very numerous 
specimens of the natural history, antiquities, and geology of 
Nithsdale, the party set out from Thornhill about ten o’clock. At 
Boatford the party turned aside to inspect the remarkable upright 
stones in the field there, the rude ornamentation on which, as Dr. 
Grierson pointed out, was of precisely the same character with 
that on the ancient cross of Durrisdeer, a portion of which is in 
his own collection, and which probably belonged to the 11th 
century. ‘The next object of interest, indeed the chief for the 
day, was Tibbers Castle, the ruins of which are at present being 
excavated under the inspection of Mr. Howitt, master of works 
to His Grace the Duke of Buccleuch. After the several points of 
interest had been inspected, Dr. Grierson read an interesting paper 
upon Tibbers Castle. In the introduction the Doctor said, ‘I will 
go back to the beginning—back to the time when these mountains 
were formed. They are Silurian, and form a basin which is the 
Vale of the Nith. Lying upon the Silurian (I think not the 
Devonian) is the Lower Carboniferous of Closeburn and Keir, a 
marine formation, in which are the remains of the characteristic 
testacea. Of vertebrate animals, all that has ever been met with 
are the flat teeth of the Psammodus, a family of fish having a 
cartilaginous skeleton. Succeeding the Lower Carboniferous, are 
sandstones. In these, excepting when in immediate connection with 
limestone, there has rarely a trace of organization been found. In 
the dark red sandstone such has never been met with; but in 
the lighter sandstone there are a few vestiges of vegetable remains. 
No indications of animals had been met with until within the 
last eight months. Those were footprints, which were recognized 
to be those of the Cheirotherium, a gigantic Labyrinthodont animal, 
whose race has long been extinct. During the formation of the 
red sandstone, and immediately preceding it, the earth was con- 
vulsed, and then issued from rents in the Silurian rocks molten 
lava. The place on which we stand was once that lava, now 
amygdaloidal trap. After the formation of the sandstones, be they 
Carboniferous, Permian, or Triassic, no other formation of solid 
rock was formed, or, if formed, it has disappeared without leaving 
a trace behind. Afterwards this valley became filled with glaciers. 
How many ages of frost there were, and what changes in subsidence 
and elevation the earth underwent, is not to be determined ; but 
the ice melted, and there were formed glacial lakes, which at times 
broke their barriers, sweeping along the débris of the rocks, and 
