Dipnoi

But the condition of the Dipnoi, which possess lungs but do not walk on land, does not support this supposition, for they possess fins which are either filamentous or fin-like, having a central axis with rays on each side.

Hormones and Heredity J. T. Cunningham 1897

It was also towards the end of the Silurian, when a period of great aridity set in, that fishes appeared related to our mud-fishes or double-breathers (Dipnoi), which have lungs as well as gills.

The Outline of Science, Vol. 1 (of 4) A Plain Story Simply Told J. Arthur Thomson 1897

The group of the lung-fishes (Dipneusta or Dipnoi) is closely connected with the older ganoids.

The Evolution of Man — Volume 1 Ernst Heinrich Philipp August Haeckel 1876

1Google “Characteristics of Dipnoi, a monophyletic group”

Panderichthys rhombolepis - The Panda's Thumb 2005

_Elasmobranchii_, _Marsipobranchii_, _Pharyngobranchii_ and _Dipnoi_ have no bony skull at all, at least in the sense in which the words have hitherto been used "(p. 571).

Form and Function A Contribution to the History of Animal Morphology