A HISTORY OF SUSSEX 



belongs to the family Chirocentridce, now represented only by the Indian 

 dorab ; a second species of the same genus, P. mantelli, has been named 

 on the evidence of a Lewes specimen in the British Museum. A lower 

 jaw in the British Museum from the Lower Chalk of Hailing has been 

 provisionally assigned to P. gaultinus, typically from the Gault of Kent. 

 To the same family belongs Ichthyodectes tninor, a fish described on the 

 evidence of a lower jaw from the Sussex Chalk in the British Museum ; 

 other species of the same genus occur in the Chalk of the neighbouring 

 counties. Scales from Lewes have been made the type of Cladocyclus 

 kwesiensis, a species of another Cretaceous genus of the same family. 

 Possibly to this family should be assigned T'omognathus mordax of Dixon, 

 a genus and species described on specimens from the Chalk of the south- 

 east of England, which may have come from Sussex ; other specimens 

 have been found at Amberley, Clayton and Southeram. 



Ctenothrissa radians^ one of three species of a Cretaceous genus 

 typifying an extinct family closely allied to the herrings, was named by 

 Agassiz (as Betyx) from Lewes specimens, the species also occurring in 

 the Lower Chalk of Clayton and Southeram. Aulolepis typus^ the sole 

 member of its genus, is another member of the same family named from 

 Lewes fossils, and distinguished from the type genus by its smooth- 

 edged scales. 



Coming to the extinct family Dercetidce, which is allied both to the 

 herrings and salmonoids, we have Leptotrachelus elongatus typified from 

 the Lewes Chalk, the specimens from which were originally described 

 by Agassiz as Dercetis. To an allied family belongs E?ichodus kwesiensis, 

 first described by Mantell as a fossil pike (Esox) ; a second species of 

 the same genus, typically from Kent, has been recently described by 

 Dr. Smith Woodward ^ as E. pulchellus, specimens from Lewes and 

 Southeram being in the British Museum collection. Hake eupterygius, 

 typified by a specimen in the Brighton Museum from Southeram 

 described by Dixon as Pomognathus, is another member of the same 

 family. The same is the case with Cimolichthys lewesie?isis, of which the 

 large spear-like teeth were long incorrectly known by the name of 

 Saurodon. 



With Acrognathus hoops, typically from Lewes, we come to the 

 scopeloid fishes (Scopelida:) ; the only other known species of the genus 

 is from the Chalk of the Lebanon. Another scopeloid is Apateodus 

 striatus, perhaps identical with the Saurocephalus striatus of Agassiz, and 

 typified by a skull from Lewes ; the two other species of the genus are 

 from the Cretaceous of Kent. 



Of especial interest is the occurrence of a fossil eel (Urenchelys 

 anglica), known by a head from Lewes in the Brighton Museum, in the 

 Sussex Chalk, since fish of this group are very scarce in the Secondary 

 strata. The other two representatives of the same genus are from the 

 Chalk of the Lebanon. 



Among the spiny-finned bony fishes the family Berychidce is 



' Op. cit. p. 194. 



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