Notas sobre el esqueleto de los Peces Neoceratodus Fosteri y Protopterus Annectens

We present here a new description and drawings of the axial skeleton of Neoceratodus fosteri and Protopterus annectens. We discuss the differences between modern and fossil forms of lung fishes in reference to the formation of vertebrae in fossil forms and the absence of such in the modern ones except for some cartilaginous remnants in the base of the neural and haemal spines and cartilaginous segments in the tail region.
We also discuss the affinities existing between some ramifications appearing in the neural and haemal spines of the dorsal and anal fins in fossil forms such as Scaumenacia.