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GREEN SAND STRATUM.

the green sandstone stratum, where they assumed the appear-ance of silicified branches inclosed in the rock. This resemblanceto branches was indeed extremely striking : an apparent corticaland woody part being distinctly observable.

Western Lines, however, afforded a great variety of specimensmuch more perfect, and this place enabled me to obtain new ideaswith respect to their origin. The conclusion which I have nowformed, is, that they belong to a species of Zoophyte, or animalpossessing a vegetable form.

Besides the forms of branches, there are here, also, numeroussmooth cylinders, of about half an inch or more in diameter, andoften several feet in length, which are very slightly tapering,seldom or ever straight, and generally mucli bent. To these aresometimes attached bulbous terminations, in which the organicstructure is very distinct, consisting of slender tubes passing lon-gitudinally through them.

Although these animal remains sometimes penetrate the solidmasses of rock in all directions, they are most abundant betweenthe beds, where they lie heaped in confusion, across each other,in prodigious multitudes. The branched forms are from less thanhalf an inch to four inches in diameter, and numerous heads, orbulbs, surrounded also by a seeming cortical envelopement, aredispersed among them. They are accompanied by another set ofappearances, which consist of figures like delineations upon thesurface of the rocks, as circles, ellipses, and parallel lines, of awhitish colour: those I afterwards found to be the various sec-tions of the external cortex of the smooth cylinders, which, whenin soft sandstone, did not remain in relief.

J he numbers of these curious organic bodies is astonishing;