fish-stage

Timmie ran down the path, as fast as his sea-boots would go: but was intercepted by Jonas Jutt, who drew him into the lower fish-stage, as though in fear of observation, and there whispered the circumstances of the departure of the _Trap and Seine_.

Doctor Luke of the Labrador Norman Duncan 1893

It was formerly regarded as a permanent gilled amphibian persisting throughout life at the fish-stage.

The Evolution of Man — Volume 2 Ernst Heinrich Philipp August Haeckel 1876

Amniotes a pro-fish stage, a fish-stage, a land-animal stage, a pro-amniote stage, and following on these a fully developed reptile, bird or mammal stage. "[

Form and Function A Contribution to the History of Animal Morphology