298 
THE GEOLOGIST. 
their flesh on, the cave could coutaiu. And this and many other arguments have been 
used expressly by Dr. Buckland to prove the caves were inhabited by the fossil animals 
while they were living. jNIr. Allen can never reconcile these facts with his bubble 
theoiy. As to caves having no mouths, it is certain they must have, or have had, if we 
find anything in their stomachs. It would be equally consistent to argue that the flies 
found in the crop of a swallow^ must have produced the stomach in which they were 
found as to argue that caverns could be filled by bones of beasts without auy oriiice for 
the beasts or the bones to get in by. — Ed. Geol.] 
TJie Portland Fissmes. 
SiE, — Though I should be sorry to do anything which would prolong 
the discussion on the Portland ossiferous fissures, I am induced to notice 
a statement, by Mr. Allen, in your July number, p. 253 ; namely, that a 
Plymouth correspondent informed him " that there was no aperture in the 
cavern " (discovered at Orestonin 1859), " and that some of the bones were 
embedded in ' compact rock.' " 
In some sense each of these assertions is correct : — 
1st. The cavern when discovered certainl}' had no aperture ; it was easy 
however to discover where there had been one. The so-called cavern was 
more correctly a fissure, originally open at the top ; but which, after the 
receipt of its varied contents, had been closed up with coarse breccia, 
consisting of large angular masses of limestone, which, from time to time, 
had fallen in from above and become cemented with carbonate of lime. 
2ndly. Some of the bones were embedded in stalagmite, which might 
truly enough be termed " compact rock," but could not possibly be con- 
founded with the true limestone. The quarrymen invariably gave it the 
distinct local designation of " callis." 
It is undesirable further to occupy your space, and indeed, it is unneces- 
sary to do so, as this subject has already been discussed in your Journal. 
See ' Geologist ' for 1859, p. 439, etc. 
I am, truly yours, 
Lamorna^ Torquay , July VI th^ 1863. W. Pengelly. 
The Bone Spear-Tiead from the Essex CoproUte Pits, figured in 
the ' Geologist ' for 1861, yage 558. 
Sir, — As the remains of man or his works, in any geological formation, 
is one of the most interesting discoveries of the present age, no manufac- 
tured article of decidedly geological age, be it ever so rude, should be cast 
aside or consigned to the cabinet without there being first brought forward 
all the evidence possible as to its age and its origin. 
Therefore when a specimen is procured, we should first show it to be one 
actually worked, and not formed by chance ; secondly, prove from what 
stratigraphical formation it has been taken ; and, thirdly, ascertain how 
far back in the scale of geological time this formation dates. 
The specimen which induces me to make the first inquiry is a bone 
spear-head, which, about five years ago, I procured from a heap of copro- 
lites belonging to Messrs. Ehodes, Smith, and Co., manure manufacturers, 
of Selby, along with sharks' teeth, Fncus contrarius, oysters, and various 
pieces of bone, all of which seem to be of the same geological age. This 
