Note 13 — Chapter I

Although we are as yet unacquainted with the internal and essential physical structure of these organic remains, which have been hitherto considered as plants, I have thought it necessary to assume the above generic name as preferable to the improbable, and at any rate merely ordinal name of Phytolithus. The Culmariæ, as I have termed them, are striated or grooved and somewhat compressed, cylindric, articulated bodies, gradually attenuating from joint to joint, mostly undivided, or simple, but occasionally bifid, and at length terminating in a point. On one of the sides they commonly possess a deep and central channel, and in some species at the joints present alternate small protuberances and cavities. Their soboliferous propagation appeared to originate from these joints, in the form of wart-like or areolate protuberances, and, unlike plants, they never seem to have produced any thing similar to leaves, flowers, or seeds.

The tessellated zoophytes, by others also considered as vegetable remains, which I have termed Strobilariæ are subcylindric and often somewhat conic, but inarticulated; some of the species protruded, as occasion required, from the centre of those tessellæ, bodies resembling hollow spines, or (as would appear from a specimen in my possession from Bradford, in Yorkshire) suckers or hollow cylinders, with circular contractile and striated mouths. The whole of these processes, when exserted mistaken for leaves, could also be withdrawn within the body of the animal, and indeed most of the casts present this quiescent or contracted state. These bodies likewise exhibit in some specimens a complicated internal structure.—Nuttall.