On some Fossil Fishes discovered by Prof. Ennes de Souza in the Cretaceous Formation at Ilhéos (State of Bahia), Brazil

Abstract

The precise extent of the Lower Cretaceous formation on the coast of Bahia (Brazil) still remains undetermined. Last year, Mr. Joseph Mawson gave to the Society an account of the deposits referable to it in the neighbourhood of Bahia itself; through Dr. Orville A. Derby, Prof. Eunes de Souza, of Rio de Janeiro, has now submitted to me some fossil fish-remains from Ilhéos, which prove that it extends at least to that point, 130 miles south of the area previously described. The specimens represent three new species, but two of them are closely related to those from Bahia, and the third appears to belong to a typically Cretaceous form of Clupeoid fish which has not hitherto been found in America. Prof. de Souza has generously presented these fossils the the British Museum (Natural History), where they form an interesting supplement to Mr. Mawson's collection. They are preserved in bituminous shale like that in which most of the fossil fishes occur near Bahia. A Cœlacanth is represented by the remains of the greater part of a skeleton of a fish about 60 centimetres long, by part of a cranium, and also by a few bones of a smaller head. The ridged ornament on some of the external bones shows that the species belongs to the genus Mawsonia , which is only known from Bahia. The head of the type-specimen is so much crushed, that it is only of interest as showing the characteristic rugose ornament on part of the cranial roof and