tinctly seen. The number is indeed truly astonishing, almost every block of stone contains many, and some of the rocks appear entirely filled with them.
Whether those having a thick cortical part, and the smooth cylinders with a speculated cortex, are different parts of the same species, representing in one case the stems and in the other the branches, I must leave to be decided by future observers; at present I am not in possession of any facts that would connect them together. They both agree in the great length of the stems, and in the general forms of the heads attached to them; but I never found the smooth cylinders of larger diameter than one inch, although I frequently observed the other four or five inches in diameter. The cortex of the former, when it was at all discernible, was always extremely thin, but that of the latter was nearly equal to the internal part; and I never found the sections of the last sort in the green sand like rings.
With respect to the smooth cylindrical fossils, whose sections formed white radiated circles, I cannot help thinking that the originals were tubular bodies, or that the animal matter which originally filled them was gelatinous, or consisted of some substance not sufficiently dense to undergo the process of silicification; in consequence of which the fossils were at first hollow, and admitted the matter which enveloped them also to fill the inside; since I constantly found the material within the radiated ring, whether sandstone or limestone, the same or very nearly so with that which surrounded it.
Although by giving full scope to the imagination, one might easily be led astray in contemplating a phenomenon so curious, yet I have no doubt but that these appearances will warrant the conclusion, that there must have existed here an immense bed of these wonderful animals, of the most gigantic size, growing like a sub-
