Narrative

Agnatha Class (or Cyclostomata) contains the lampreys and hagfish. They are characterized by having a sucking mouth and the lack of a lower jawbone. Although most older biology books separate the phylum chordata into five major classes (fish, amphibians, reptiles, birds, and mammals), recent thinking has been to divide the fish group into three separate classes (lamprey, sharks & rays, and normal bony fish).

Taxonomy

References