Sp. char.—Shell (cast) discoidal, somewhat inflated, rather rapidly increasing. Whorls somewhat inflated, very convex on the periphery, less convex on the sides, rounded near the umbilicus. Umbilicus moderately wide, occupying nearly one-third of the diameter of the shell. Number of whorls and amount of inclusion unknown. Height of outer whorl rather more than one-third of the diameter of the shell. Each whorl ornamented with ahout 20 short, thick, umbilical ribs, each of which commences at the suture, extends radially or with a very slight forward inclination over one-fourth of the width of the lateral area, and terminates in a radially elongated tubercle.

From the foregoing remarks it will be seen that the Middle Cambrian, as at present defined, is characterized by having numerous Life Zones in which, usually, species of the genus Paradoxides, or of some closely allied forms, may be considered the dominant organisms. Up to the present the genus Olenellus, so typical of the Lower Cambrian rocks, has not been foundindirect association with Paradoxides, but some of the associated genera are equally characteristic both of the Lower and of the Middle Cambrian.

There have been many suggestions respecting a continental connection of the West Indies, but this is the first attempt made to restore the Antillean lands. It is based upon the slowly accumulating evidence of great systems of submerged valleys, or fjords extending from the commonly buried lower reaches of all the great rivers, upon the terrestrial deformation involved in the changes of level over large regions and upon the distribution of the characteristic forms of life. The present investigations confirm and amplify the history of the coastal plain of the northern continent.

Every geologist is familiar with the name of Storeton Quarry, which may fitly be termed the “home of the Cheirotherium”, celebrated as being the scene of the earliest discoveryinEngland of the fossil footprints, first described by Messrs. John Cunningham and James Yatesin1839.

Fifty years' study of these footprints has left their origin, so faras exact identification with any known animal is concerned, a matter of as much mystery as when Sir Eichard Owen gave attention to the subject in his classical work on “Palaeontology”.

The discovery of an Ammonite (Oppelia subradiata, Sow., from Dundry, now in the British Museum) with the Aptychus in situ closing the orifice, would seem sufficient to set all doubts at rest as to the true nature of that body, viz. that of an operculum. Many of the writers on the continent, however, have not seen that specimen, which unfortunately is unique, and are inclined to attribute to the Aptychus other offices, because:—