CORRESPONDEirCE. 
9' 
Professor Buckland stated as liis opinion, that the mass of matter of which 
the Island of Portland is composed on drying cracked and so formed 
these fissures. But how is it these fissures did not extend up to the sur- 
face-soil, where the evaporation must have been greatest, and where there 
appears no trace of them? Several teeth and a tusk of an elephant have 
recently been discovered in the dirt-bed of the Portland quarries." 
The truth of these facts mentioned in the ' Current Notes,' which, in all 
material circumstances, are similar to the facts mentioned in the ' Times,' 
has been confirmed to me by Captain Manning himself, who has several 
times shown me, at Portland Castle, human and other bones, and amongst 
them those of the elephant, which have been discovered in the fissures of 
the Portland rock. Captain Manning stated that these fissures did not 
extend to the surface of the rock. 
The truth of these geological facts may be easily ascertained by any 
person visiting Portland Island. 
If human and other bones have been found in fissures which have no 
communication with the surface of the earth and are covered with solid 
stone, must they not have entered the rock before its consolidation, and, 
consequently, when it formed part of the bed of the sea? And must not, 
therefore, the men and animals to whom the remains belonged have inhabited 
some other dry land, which probably no longer exists? And does not this 
render probable the opinion of M. Cuvier, expressed in the following 
words : — " I conclude, with MM. De Luc and Dolomieu, that if there be 
any fact well established in geology it is this, that the surface of our 
globe has suffered a great and sudden revolution, the period of which 
cannot be dated further back than five or six thousand years. This revo- 
lution has, on one hand, engulfed and caused to disappear the countries 
formerly inhabited by men and the animal specie? at present best known ; 
and, >on the other, has laid bare the bed of the last ocean, thus Converting 
its channel into the present habitable earth "? 
The period of this revolution, which MM, Cuvier, De Luc, and Dolo- 
mieu believe to have been effected by an interchange of land and sea, 
synchronizes very nearly with the one usually assigned to the Mosaic 
Deluge. Your obedient servant, 
Thos. D. Allen. 
Rectory, North Cerney, Cirencester, Jan. 23, 1863. 
Glyptolepis — Dura Den. 
Deae Sir, — The Eev. Mr. Mitchell, in his communication regarding 
this genus in your number for February, omits to mention that tlie dis- 
covery that what formerly used to be named Huloptychius Flemingi is 
in reality a species of Glyptolepis, is by no means quite new. 
The attention of Professor Huxley, Mr. Robert Walker, of St. Andrew's, 
and myself, having been directed to the Dura Den fishes, in consequence 
of rather extensive excavations in the Den, which, through the kindness 
of Mrs. Dalgleish, were allowed to be made in the summer of 1861, for 
furnishing specimens to the St. Andrew's Museum, we seem indepen- 
dently to have arrived at that conclusion. Towards the end of last 
summer, in writing me, of date 24th September, 1862, Mr. Walker states, 
"What was rather a curious coincidence," etc., " I left the Museum with 
a pretty strong conviction that the scales of Holoptychius Flemingi and 
Glyptolepis appeared to be one and the same, when here comes your letter 
