The term Cambrian (from Cambria, the ancient name of Wales) was originally employed by the Rev. Professor Sedgwick to include a great series of fossiliferous and other rocks occurring below the Bala Limestone in North Wales. Sir Charles Lyell adopts to a certain extent this classification, dividing it into Upper and Lower Cambrian.

I have lately received, from Mr. James Armstrong of Glasgow, some very beautiful examples of the detached teeth of Dithyrocaris from Lanarkshire and Renfrewshire, and also specimens of Ceratiocaris from Lesmahagow (the latter collected by Mr. J. Slimon); and they seem to possess so much interest, that a description of them will doubtless be welcome.

Lindley and Hutton, in their ‘Fossil Flora’ (vol. i. p. 181), give a plate and description of some specimens, termed by them Polyporites Bowmanni, which were found by the late Mr. J. E. Bowman, F.L.S., in the Carboniferous strata, near the entrance of the Vale of Llangollen, in the county of Denbigh.