Dr. H. Woodward—Eurypterus in the Coal-Measures. 277 
be needed to crush the chalk, a problem which Mr. O. Fisher might 
easily have faced before offering an hypothesis so remote from proba- 
bility. But even if he had faced it we should be no nearer. ‘There is 
no sign whatever of mere crushing in these chalk cliffs and great 
chalk masses. The chalk in them and the lines of flint in them are 
quite intact, and so are the beds of consolidated gravel and finely 
laminated sand which in many places are adherent to them. We 
should expect if the pressure had been sufficiently great to be efficient 
at all that it would have crushed these chalk beds into powder, and 
not curved them and twisted them in this way, or broken them off 
with sharp edges. The whole process seems to me utterly fantastic 
and impossible. I am not alone in thinking so. In this instance I 
quite agree with Mr. C. Reid when he says: ‘‘The Rey. O. Fisher’s 
theory of the forcing up of the beds by irregular deposition of masses 
of material on their surface seems inadequate to the formation of con- 
tortions on so vast a scale. It is doubtful whether anything less 
than a mountain piled on the surface at Trimingham would be 
sufficient for the contortion of 200 feet of underlying strata.”? This 
is quite judicious, although it understates the difficulty, but in 
the face of such a statement what are we to say of Mr. Reid’s own 
theory? After thus demolishing the Rey. O. Fisher’s notion that the 
chalk dislocations were due to the differential pressure of super- 
incumbent masses of strata as quite inadequate, he proceeds, without 
any attempt at a physical analysis of the conditions of the problem, to 
apply the very same kind of explanation himself, only substituting ice 
for beds of rock or sand or clay. Assuredly, nothing can well be 
more inconsequent, for it merely adds to the difficulties instead of 
diminishing them. Let us analyze his argument. The distinction in 
Mr. C. Reid’s mind seems in some way to rest on a notion that while 
the postulated superincumbent rocks, sands, or clays here referred to 
would be ex hypothesi stationary, ice is in a measure mobile, and he 
says the explanation of the broken and contorted condition of the chalk 
is only possible on the hypothesis of ‘a lateral thrust, or of a sliding 
pressure from above.” 
(To be continued.) 
V.—Two New Species or Houryprervs From THE CoaL-MEASURES 
or Inkeston, DrrBysHIRE. 
By Henry Woopwarp, LL.D., F.R.S., V-P.Z.8., F.G.8. 
(CEGAVINET, Sexes) 
Y the kindness of Mr. Henry A. Allen, F.G.S., of the Geological 
Survey of England, three examples of Hurypterus, in clay-iron- 
stone nodules, showing impression and counterpart, together with 
a fragment of a fourth example, all from the Coal-measures to the 
north-west of Jlkeston, have been most obligingly lent me for 
description by their discoverer, Dr. L. Moysey, M.A., of St. Moritz, 
Ilkeston Road, Nottingham. 
Remains of Eurypterus are extremely rare in the Coal-measures 
The earliest Carboniferous ELurypterus discovered and described was 
