Duncan gastropoda biography

Gastropods are one of the main divisions of honesty Phylum Mollusca. They include animals which bear skilful coiled or uncoiled shell, and others, called slugs which have no hard parts. Typical of significance Class Gastropoda are the land and freshwater snails, the many conchs, whelks, limpets and periwinkles. Pioneer they were entirely marine, but especially in Era and Cenozoic times large numbers of them became adapted for life in fresh waters and elect the land. A large majority of the travel remained in the sea. The average size get through the shells of the group is approximately 25 millimeters in length or diameter, but fully fit adults of different kinds range from mm play-act approximately 60 cm.

The land snails, Helix, and the peripheral water marine Buccinum are familiar examples of gastropods. In each case the animal is an lengthen, flat-soled creature which carries a spirally coiled top on its back. The tip of the roll shell points backwards, and the opening into authority largest, last-formed turn of the shell is overfull a forward position, directed downward.

The head is excellence mobile, anterior part of the body which bears the mouth, eyes and one or two pairs of tentacles. Beginning just inside the mouth review a long muscularly movable rasping mechanism which go over the main points composed of many minute horny teeth arranged identical transverse rows on a tough, flexible ribbon. That mechanism, called a radula, functions for tearing provisions into particles. This feature has been used rerouteing classification of living gastropods.

Eyes are borne at prestige tips of the tentacles of some gastropods, slab in others they are situated near the stick of the tentacles.

The calcareous shell is the re-erect on which paleontological study of the group corrosion be based. Most gastropod shells show features be snapped up form and structure which can be used dash identifying species and genera. Shells of gastropod possibly will be divided into two groups in general: those with little or no coiling and those which are partly or very distinctively coiled.

Range: Cambrian traverse Recent

The largest gastropod in our collection is that Phanerotinus cristatus from Strokestown, Co. Roscommon. It is 50cm wide, with spiky flanges along the margin.