The fishes that we have so far been considering-orphans of the past they might be termed, as they have no living relatives-were little fellows; but their immediate successors, preserved in the Devonian strata, particularly of North America, were the giants of those days, termed, from their size and presumably fierce appearance, Titantichthys and Dinichthys, and are related to a fish, ceratodus, still living in Australia.
"Animals of the Past"
Frederic A. Lucas
The ceratodus of certain Queensland rivers has one lung; though, I was told by the experts in Queensland, it is not a "mud-fish," and never lives in dry mud.
"The Story of Evolution"
Joseph McCabe
When the skeletons of fishes of the ceratodus type were discovered in the Devonian rocks, it was felt that we had found the fish-ancestor of the land Vertebrates, but a closer anatomical examination has made this doubtful.
"The Story of Evolution"
Joseph McCabe