...small rounded pehbles ; in others the angles are unbroken. Both varieties are covered with a -erust of greenish earth of the same nature with the green...which the upper surface in contact with the sand is considerahly decomposed to the depth of ahout a foot, and its fissures and numerous small tuhular 'cavities...

...of greenish earth of the same nature with the green particles in the sand. The angular flints appejr to have been derived from the partial destruction...numerous small tubular cavities (the latter derived appa:ently from the decay of organic substances) are filled with granular particles of the green earth...

...others the angles are unbroken. Both varieties are royered with a crust of greenish earth of the lame nature with the green particles in the sand. The angular...depth of about a foot, and its fissures and numerous sniall tubular cavities (the latter derived apparently from the decay of organic substances) are filled...