48 Correspondence—Dr. H. Woodward. 
Both these veins of shale, but especially the thinner one, have 
a rudely columnar structure at right angles to their direction. 
Excepting that this shale is a little more indurated and more like - 
slate in its constitution, it is similar to the Cambrian green shales 
that overlie the basal conglomerate. These veins are in my view 
undoubtedly part of the Cambrian shale entangled in the granite, so 
that the granite must be post-Cambrian.” 
Now, Sir, these veins are perfectly well known to all who have 
examined the sections at Porthclais, but it has been reserved for Mr. 
Reade to venture to call them Green Cambrian Shales. Those who 
have examined these veins with any care have had no difficulty in 
recognizing in them the ordinary behaviour of igneous rocks, and in 
proving after a microscopical examination that they are diabase 
dykes! Such dykes, as is well known, are common in the Dimetian, 
and they have been frequently referred to in my papers. Mr. Reade 
would therefore have acted more wisely, if, before publishing his 
views, he had taken the trouble to read more of what had been 
written on the subject, and also had consulted a petrologist as to the 
nature of the rocks he was dealing with. 
Henpon, Dec. 3, 1887. Henry Hicks. 
ON ETOBLATTINA, A LARVAL COCKROACH FROM THE COAL- 
MEASURES OF KILMAURS, AYRSHIRE; DISCOVERED BY MR. 
LINTON, OF KILMARNOCK. 
My attention has been called by Mr. Robert Kidston, F.G.S., to 
a serious omission made by me in my notice of Htoblattina Peachit 
in the GronocicaL Macazrne for October, 1887, p. 432. 
It is true that the specimen was forwarded to me by my friend, 
Mr. B. N. Peach, of the Geological Survey of Scotland, but I am 
now informed that it was found by a private geologist, Mr. Linton, 
of Kilmarnock,’ and he it was (and not the friend who sent it to 
me) whom I should have specially mentioned as being the discoverer. 
I regret exceedingly my carelessness in not making further inquiries 
of Mr. Peach as to its ownership before setting out to describe this 
interesting Carboniferous treasure, and I take this opportunity to 
thank Mr. Linton most cordially for placing it so generously at Mr. 
Kidston’s disposal for examination. We are all so deeply indebted 
to the persevering labours of such private geologists, as Mr. Linton, 
that I, for one, would be the last to omit to award them their full 
meed of honour. 
129, Beaurorr Street, S.W. Henry Woopwarp. 
1 This gentleman entrusted it to Mr. Kidston to be described. Mr. Kidston 
transferred it to Mr. Peach, who subsequently transmitted it to the writer—H.W. 
Western AvsTRALIAAWA—Mr. Harry Pace Woopwarp, F.G.S., F.R.G.S. 
(eldest son of Dr. Woodward, F.R.S., V.P.G.S.), who served for more than three years under 
Mr. H. Y. L. Brown, F.G.S., as Assistant Government Geologist in South Australia, has 
been appointed by Her Majesty’s Secretary of State for the Colonies to the post of Govern- 
ment Geologist for Western Australia. Only a very small portion of this, the largest of the 
Australian Colonies, has at present been examined by a geologist. Mr. Woodward left for 
Perth on the 2nd of December last.—Z7he Trmes, Dec. 8, 1887. 
