[Download] "Beautiful Shells of New Zealand" by E. G. B. Moss * eBook PDF Kindle ePub Free

eBook details

Title: Beautiful Shells of New Zealand
Author : E. G. B. Moss
Release Date : January 23, 2010
Genre: Life Sciences,Books,Science & Nature,
Pages : * pages
Size : 655 KB

Description

Before the study of shellfish, or molluscs, was conducted on the scientific principles of the present day, shells were classified as univalves, bivalves, and multivalves. The univalves were shells in one piece, such as the whelk; the bivalves those in two pieces, such as the mussel or oyster; and the multivalves those in more than two pieces, such as barnacles or chitons, barnacles, however, being no longer classed with shells. The highest of the five types, or natural divisions, of animals are the Vertebrata, the Mollusca, and the Annulosa. The vertebrates usually have vertebrae, or jointed backbones, and from this the highest division takes its name; but the real test is the colour of the blood, which in the vertebrates is always red.