{ } {145} { I. CYCLOSTOMATA. } AGNATHOSTOMATA. { Lampreys and } Without biting { Hag-Fishes. } jaws. ICHTHYOPSIDA. { Breathing by gills at some { } period of life. { } { II. PISCES. } { True Fishes. } ANAMNIOTA { } No embryonic covering { } or amnion. { } { III. AMPHIBIA. } { Newts, Frogs, and } { Toads. } ANALLANTOIDEA. { } No embryonic respiratory { } organ or allantois. { } GNATHOSTOMATA. { } With biting } jaws. { IV. REPTILIA. } { Lizards, Snakes, } { Turtles, and } { Crocodiles. } { SAUROPSIDA. { } AMNIOTA. { { } Amnion present. { { V. AVES. } { { Birds. } { } ALLANTOIDEA. { } Allantois present.{ VI. MAMMALIA. } { Hairy Quadrupeds. }