193 
noticed in Great Britain. Probably the passage of carbon- 
iferous into the overlying permian beds is more apparent 
than real, and the bed of breccia doubtless shows a period 
of disturbance, but in the whole course of my observations, 
extending over thirty years, I have never seen anything 
before which appeared so nearly to prove the passage of the 
one into the other as this section does.” 
Since the above was written unfortunately nothing more 
has been done to his knowledge to prove the section. The 
600 feet of coal m.easures lying above the Spirorbis lime- 
stone are the highest carboniferous strata yet met with, but 
they have not yet been clearly proved to pass upwards into 
the permians. This remains to be done. 
A short time ago he had again visited the Canobie sec- 
tion in company with his friend Mr. J. W. Kirkby, and in 
addition to the Spirorbis carbonarius formerly found in the 
limestone, that gentleman recognised in the shales near it 
Athracomya ? Beyrichia arcuata (Bean), Spirorbis Jielictres 
(Salter), and a single specimen of a long entomostracan not 
to be determined from its state of preservation. 
It has been stated that the occurrence of the Spirorbis 
carbonarius, which is well known as being found in car- 
boniferous rocks of aJl ages, from the Bardiehouse limestone 
to the Ardwick beds, would by itself have little value in 
identifying strata 200 or 300 miles apart. It was for- 
merly attempted by a very eminent geologist to prove that 
the Bardiehouse limestone occupied a position above the 
millstone grit, simply because it contained the Spirorbis 
and some other common coal fossils. No doubt the diag- 
nostic value of such fossils has considerably diminished at 
the present day ; but in addition to containing the Spirorbis, 
this limestone on breaking exhibits a singular porcelain-like 
appearance, a semiconchoidal fracture, and a mottled charac- 
ter, which are not recognisable in other carboniferous lime- 
stones so far as his experience went ; and it is always found 
