TERTIARY FISHES. 
9—249 
writer has not therefore been able to assure himself of the distinctness of the fossil 
form ; but as such distinctness is probable, it is proposed to provisionally regard the 
latter as a new species, under the name of II. palmindicus. 
Tlie occurrence of a species of Jleterohranchus in the pliocene of India is ex- 
tremely interesting as affording another instance of the probable migration of 
existing African genera from an Oriental centre of distribution. 
Subfamily II. PROTEBOFTEBJE. 
Group A. BAGRINA. 
Characters — The anterior and posterior nostrils are remote from one another. 
Genus I. CHRYSICHTHYS, Bleeker.^ 
Characters. — Teeth on the palate in two lateral portions; jaws equal in length, 
or the upper the longer ; skull relatively broad, and the bones of the upper part of 
the cranium usually with a cancellous structure. Clarotes is distinguished by very 
slight characters. 
Eistribution. — The genus is confined at the present day to tropical Africa ; seven 
species are recorded by Giinther,^ the largest of which attains a length of fifteen 
inches. Clarotes is also African, and is known by one species. 
Species. Cheysichthys (?) theobaldi, n. sp. nobis, 
(From the Siwaliks.) 
History. — The specimen on which this species is founded is described for the 
first time. 
Cranium. — The hinder portion of the cranium of a siluroid represented in plate 
XXXVII. fig. 4 was collected by Mr. Theobald from the Siwaliks of the Punjab. 
The supraoccipital and frontal region is well preserved, but the basicranial axis has 
been twisted to the left side, and a portion of tlie upper surface of the cranium 
displaced below the frontals. The whole of the upper cranial bones are coarsely 
cancellated, thus presenting an approach to a true sculpture, and showing that the 
overlying skin was comparatively thin. In figure 5 there is represented the skull of 
the existing Chrysichthys macrops^ and a comparison of this figure with that of the 
fossil will show how extremely close is the resemblance between the two. Thus 
both exhibit the same relatively wide cranium, with the short supraoccipital process 
(sup.), the long frontal vacuity (/;), and the cancellous upper surface of the bones. 
Affinities. — The fossil indicates an individual of about two feet, or rather more, 
in length, and its close resemblance to Chrysichthys leaves but little doubt that it 
belongs either to that or a closely allied genus. The relatively great width of the 
cranium, the shorter supraoccipital process, and the cancellous structure of the 
cranial bones at once distinguish it from Bagrus : but Clarotes is too closely allied to 
Chrysichthys to admit of distinction in the case of specimens as imperfect as the 
present one. 
1 “ Ichthyol. Archipel. Ind. Prodromus — Siluroidei,” p. 60 (1858). 
2 “ Catalogue of Fishes,” vol. V pp. 71-73, and 430-431 (1864). 
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