HAGFISH

Common Name: "no jaws"

Distinguishing features: Agnatha are characterized by lacking a jaw and by having a notochord (a flexible rod-shaped body) in both larvae and in adults. They also lack paired fins and they have seven or more paired gill pouches. They are cold blooded, and they have a cartilaginous skeleton. Agnatha do not have an identifiable stomach or any appendages. Fertilization and development are both external and their heart contains 2 chambers.

Examples include hagfish and lampreys. 

Sources: http://en.wikipedia.org/wiki/Agnatha

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