gill slits
Externally
Agnatha is a superclass of the phylum Chordata. It contains the jawless fish. Two common examples of this would be the lamprey and the hagfish.
Agnatha are ancient jawless fish that include lampreys and hagfish. They are also probably the earliest vertebrates and have ectoderm.
skin
without jaws
Class Agnatha
Agnatha, such as lampreys and hagfish, have a two-chambered heart. The heart consists of an atrium and a ventricle, which pump blood through the circulatory system.
with gills; they're fish!
I don't know but i will do some research...
jawless fish. not very common today, but they were in the past.
no they have large bonelikes structures called the stonnes.
Agnatha means 'no jaws', and they really don't have jaws, although they do have teeth. They also have no stomach, and no boney skeleton. Their skeleton is cartilagineous, like the elasmobranchs.