TRANSACTIONS OF SECTION GC. 1005 
\ of the officers of the Geological Survey will be especially directed. The geological 
surveyors of Scandinavia have been so fortunate as to detect, in rocks of an ex- 
tremely altered character, a number of fossils sufficiently well preserved for generic 
and sometimes even for specific identification. Failing the occurrence of such a 
fortunate accident, I confess that it has always appeared to me that the disturbances 
to which these Highland rocks have been subjected are so extreme, and the difficulty 
of making out the original planes of bedding so great, that but little can be hoped 
for from general sections constructed to show the relations of the rocks of the 
Central and Sotithern Grampians to the fossiliferous deposits of the North-West of 
Sutherland. 
Lying unconformably upon these Archean crystalline rocks in our North-West 
Highlands we find great masses of arkose or felspathic grit, with some conglomerates, 
the whole of these well-stratified deposits attaining a thickness of several thousands 
of feet. These rocks, in their characters and their relations, so greatly resemble the 
‘Sparagmite Formation’ of Scandinavia, that it is impossible to refrain from 
drawing comparisons between them. The Scandinavian formation, however, in- 
cludes calcareous and slaty deposits, which are wanting in its Scottish analogue. 
The ‘ Sparagmites’ of Scandinavia, as a whole, appear to underlie strata containing 
Cambrian (Primordial) fossils, but in the very highest portion of the ‘ Upper 
Sparagmite Formation’ of Southern Norway there have been found, according to 
Kjerulf, specimens of Paradoxides. 
The Scottish formation has, on the other hand, yielded no undoubted organic 
remains. Murchison, on the ground of its unconformable infraposition to his 
Silurian strata, and its resemblance to certain beds in Wales which he called 
Cambrian, referred it in his later years to that system. Although an identification, 
based on such grounds, must be admitted to be of small value indeed, yet the dis- 
covery: of ‘ Primordial’ fossils in the very similar rocks of Scandinavia may be 
admitted to lend it some slight support. In the present state of our knowledge, 
however, it is surely wiser to admit that the question of the age of these beds is 
still an open one, and to call it by the name suggested by Nicol—‘ The Torridon 
Sandstone.’ Kjerulf believes there is evidence that the Scandinavian Sparagmite, 
in places, passes horizontally into true gneiss, and similar appearances are not 
wanting in the case of our Torridon Sandstone. 
Concerning the overlying formation of quartzites and limestones, much yet 
remains to be made out. Nicol, Lapworth, and the officers of the Geological 
Survey, have shown it to be made up of three principal members—the identity 
of which cannot be mistaken although different names have been assigned to them. 
While Nicol estimated the total thickness of this formation at from 800 to 800 feet, 
however, and Lapworth places it at the smaller of these amounts, the officers of the 
Survey believe it to be no less than 2,000 feet thick. 
Even greater uncertainty still exists as to the exact geological age of this im- 
portant formation. Murchison, who in his later years made ‘Silurian’ a mere 
synonym for Lower Paleozoic, was no doubt right in regarding these rocks as 
being of that age. I have no intention of attempting to flog that dead horse— 
the controversy concerning the names which should be applied to the great systems 
containing the three faunas which Barrande so well showed to be present in the 
Lower Palzozoicrocks. That controversy, commencing, it must be confessed, with 
some tragic elements, has long since passed into the sphere of comedy, and now bids 
fair, if still persisted in, to degenerate into farce. Little, if anything, has been 
added to the work of Salter in connection with these fossils of the Durness 
limestone. With their abundance of that remarkable and aberrant mollusc, 
Maclurea, they can be paralleled with no other British or even European deposit, 
unless it be the Stinchar limestone of the Girvan district. Salter thought that this 
remarkable Scotch formation had its nearest analogues in the Calciferous sandstone 
and the Chazy limestone of North America. As those rocks contain ‘ Primordial ’ 
forms of Trilobites, they must probably be regarded as either of Cambrian age, or 
as constituting a link between the rocks containing Barrande’s first and second 
faunas respectively. Under these circumstances, it isa piece of welcome intelligence 
that the officers of the Geological Survey have succeeded in obtaining a rich and 
