x 
96 Correspondence—Mr. Alex. Somervail. 
to penetrate the “dim and distant future.” My descriptions of the 
older Archean rocks and their distribution are not materially affected 
by the theory of mechanical metamorphism; but we must of course 
cease to construct time-series out of them. Alas! how many a 
stately time-edifice goes down before the blows of those gods of 
the hammer, Lehmann and Lapworth ! Cu. CaLLaway. 
THE SERPENTINE OF THE LIZARD. 
Sm,— Would you kindly allow me to reply to the letter of Prof. 
Bonney in your January issue on the above subject Hegel y my 
alleged ‘two slight errors.’ 
1. I think the Professor's mind has very naturally (perhaps 
without reference to the map) reverted to the south end of the 
Pentreath Beach, where the hornblende schist occurs in conjunction 
with the serpentine, which he has so ably and minutely described ; 
but the dyke in question is at the north, or Kynance end, near a 
large exposure of banded gneissic rocks forming the foreshore of 
Holestrow, similar to what occurs in many other localities described 
by the Professor as “granulitic,” as at Caerleon and Kennack, at 
the west end of which latter Cove the dykes cutting the serpentine 
are seen to coalesce with the “ granulitic” rocks forming the 
foreshore. 
2. For my own part I know of no “granulitic group” in the 
whole area with igneous rocks involved or included in it, but a 
group of rocks to which the term “ granulitic”” might be applied, 
which every evidence seems to point at as having a common igneous 
origin, although differing widely from each other; neither do I know 
any separation between these and the hornblende schists save in the 
extremes of their compositions, both of which are frequently mingled 
together in the same dykes. 
I quite agree and deeply feel with Prof. Bonney the very great 
difficulties connected with some of these Lizard rocks, such as the 
explanation of the banded gneissic series which has been so philo- 
sophically dealt with by Mr. Teall; and it was for this very reason 
that I ventured my short communication on the dyke and its lessons, 
in the hope that it might throw some little additional light on these 
gneissic and other rocks, which I have always regarded as presenting 
very much that is problematic. ALEX. SOMERVAIL. 
59, Frrrt Street, Toravay, Jan. 9th, 1889. 
MISCHLGLANEHOUS. 
———.__—_ 
AppEnpA.—In the section illustrating Prof. Hughes’ paper, Guot. 
Mac. Jan. 1889, p. 9, the asterisk indicating the third fossil locality 
mentioned in the text has been omitted. The spot referred to is 
immediately under the Bronllwyd Grit, vertically below the Y of 
that word on the diagram. 
