United States or United Kingdom ? Vote for the TOP Country of the Week !


Among the shells which abound in this cliff are Paludina lenta and various species of Lymnea, Planorbis, Melania, Cyclas, Unio, Potamomya, Dreissena, etc. Wood have found the jaws, teeth, and hard shining scales of the genus Lepidosteus, or bony pike of the American rivers. This same genus of fresh-water ganoids has also been met with in the Hempstead beds in the Isle of Wight.

Snails cling to the sides, and clean away and consume all this vegetable growth. The Lymnea is among the most efficient, but unfortunately is destructive, by eating holes in the young fronds of the larger plants, and thus injuring their appearance. To this objection some other varieties of snail are not open. The Paludina and Planorbis are the only kinds which are trustworthy.

Melania turritissima, Forbes. a. Fragment of carapace of Trionyx. b. c. Bulimus ellipticus, Sowerby. Helix occlusa, Edwards. Paludina orbicularis. Planorbis discus, Edwards. Lymnea longiscata, Brand. Chara tuberculata, seed-vessel. d.

I have shown that there is a fluviatile deposit in the valley of the Niagara, containing shells of the genera Melania, Lymnea, Planorbis, Velvata, Cyclaz, Unio, Helix, etc., all of recent species, from which the bones of the great Mastodon have been taken in a very perfect state.

The prevalence of salt-water remains is most conspicuous in some of the central parts of the formation. Helix labyrinthica, Say. Neritina concava, Sowerby. Lymnea caudata, Edw. Cerithium concavum, Sowerby. Searles Wood in Hordwell Cliff. It is also met with in Headon Hill, in the same beds.