Representative Types of Chondrichthyes | Vertebrates | Chordata | Zoology
In this article we will discuss about the representative types of chondrichthyes with the help of a suitable diagram. Sharks and Rays: 1. Heptanchus: Heptanchus is regarded as the most primitive shark. It is long bodied and slow moving. There are seven pairs of gill-clefts. Hexanchus, another primitive shark, has six pairs of gill-slits. Mouth is sub-terminal and there is [...]