Reviews—Austin— On the Millstone Grit. 5a 
considered as more typical than that of any other district, as in Glou- 
cestershire and Somersetshire this formation, composed of sandstone 
grit, and conglomerate, attains a thickness of 2,500 feet with but very 
slight traces of coal. In the Midland Counties, on the contrary, as 
Derbyshire and Lancashire, and even still further north, it contains 
intercalated beds of shale, impure limestone, and coal, accom- 
panied by a corresponding change in the fossil contents. 
The character of this formation, as seen in the Flintshire Coal- 
field, Shropshire, has already formed the subject of an article in the 
GroLoeicaL MaGazine for March 1865, p. 107. Mr. Prosser de- 
scribes the Millstone Grit of this district as highly fossiliferous, but 
the specimens are not well preserved. 
As to the thickness of the Millstone Grit at Kingswood Hill 
near Bristol, Mr. Handel Cossham has clearly demonstrated that 
this deposit belongs in reality to the Lower Coal-measures, and 
is there known as the ‘Holmes Rock,—an important evidence of 
the further extent in depth of the Bristol Coal-field. (See Gerot. 
Maae., No. IX., p. 110.) 
After treating of the Millstone Grit, its climate, and origin, the 
author proceeds to describe its fauna :—‘ A very great proportion of 
the organic remains,’ says Mr. Austin. ‘obtained and figured in this 
contribution to its history, I believe are new in species, though but 
few of them are so in genera.’ The number of new species és very 
remarkable (39 out of 47), and on this point we feel extremely 
doubtful, especially as the descriptions are exceedingly meagre, and 
the figures do not help us much more. We should almost incline 
to the opinion that some at least were established on fragments of 
well-known species which our veteran friend has failed to recog- 
nize. 
The nomenclature is seriously at fault, and we strongly advise 
the author, in justice to himself, to undertake the revision of the 
specific names, and the figures of many of his new species also. 
An account of the economic uses of the Millstone Grit, and some 
interesting remarks on the dip of the beds, are deserving of atten- 
tion and perusal. 
IV.—TueE SiILuRIAN FORMATION IN THE PENTLAND His. By 
G. C. Haswe.1t, Hon. Sec. G.S.E. Edinburgh: W. P. Nimmo. 
1865. Pp. 47. 4 Plates. 
LL visitors to Edinburgh know the Pentland Hills, which, 
closing in the horizon to the south, contribute not a little to 
the beauty of the magnificent panorama which surrounds the capital 
of the North. ‘They are composed chiefly of felstone and ash with 
coarse conglomerates, grits, and sandstones of the Upper Old Red 
Sandstone age. In these localities the underlying Silurian rocks 
come to the surface, and to one of these, the famous Habbie’s How, 
beyond Carlops—the scene of Ramsay’s ‘Gentle Shepherd ’"—Mr. 
Haswell has devoted some attention. The results of his observa- 
tions he read to the Edinburgh Geological Society, and has now 
published. We almost regret that he has hurried himself into print, 
