PALAEONTOLOGY 



Burham. Of the porbeagle sharks the existing genus Lamna is repre- 

 sented by L. appendiculata in the Lower Chalk, Chalk-marl and Gault of 

 the county, L. semiplicata at Charing and Rochester, and L. sulcata at 

 Rochester ; and the extinct Odontaspis by O. mantelli at Burham, Charing, 

 Dover, Gravesend and Greenhithe, and O. angustidens at Dover and 

 Hailing, neither of these species being typically Kentish. Finally, the 

 broad-toothed sharks of the Cretaceous genus Gorax are represented in 

 the county by remains of the widely spread C.fakatus, which have been 

 recorded from the Chalk of Bromley, Greenhithe, Margate and Maid- 

 stone. 



Among the chimsroid fishes a lower jaw in the British Museum 

 believed to be from Kent has been described as Ischyodus incisus, but the 

 generic reference is open to some degree of doubt. In the allied genus 

 Edaphodon the species E. mantelli, typically from Sussex, is also known 

 from Burham, Charing and elsewhere in Kent, and the Sussex E. 

 agassizi is likewise recorded from Burham. The Sussex Elasmodectes 

 ivilletti is also known from Burham. The fringe-finned ganoids are 

 represented in the Lower Chalk of Dover and Maidstone by the well 

 known Macropoma mantelli, a species first described from Sussex. 



In the sturgeon group the existing family Polyodontidce is represented 

 by the genus and species Pholidurus disjectus, described by Dr. Smith 

 Woodward on a fragment of the tail from Gravesend in the collection of 

 the British Museum. Quadrangular polished scales of the general type 

 of those of the ganoid Lepidotus in the same collection from the grey 

 Chalk of Folkestone have been provisionally assigned to that genus with 

 the name of L. pustulatus. Among the allied pycnodont ganoids a speci- 

 men in the British Museum of the lower dentition from Hailing has 

 been made the type of Ccelodus Jimbriatus, while the continental Pycno- 

 dus (?) scrobiculatus is represented in the same collection by the palatal 

 dentition from Charing. In another group of ganoids — the Eugnathidce 

 — the genus and species Neorhombolepis excelsus have been established by 

 Dr. Smith Woodward on the evidence of a specimen from Hailing, 

 while a Burham ichthyolite has been made the type of N. punctatus. 

 To the same family belongs Lophostomus dixoni, typically from Sussex, 

 but also known in the Maidstone Chalk. The spear-like teeth of the 

 widely spread Protosphyrcena ferox occur at Burham, Cuxton and else- 

 where in the county, and those of P. minor at Burham ; a third species, 

 P. compressirostris, has been founded by Dr. Smith Woodward on the 

 evidence of a beak in the British Museum from the Kentish Chalk. In 

 another family of long-beaked ganoids, the Aspidorhynchidce, the Sussex 

 fish Belonostomus cinctus is known in Kent by remains from Burham. 



Passing on to the herring-like fishes of the family Elopidce, we find 

 the genus and species Elopopsis crassus typified by remains in the Brigh- 

 ton Museum from Mailing, and also represented by a Kentish specimen 

 in the British Museum. In another genus of the same family (typified 

 by the Sussex O. lewesiensis) we have Osmeroides levis described on the 

 evidence of remains from Burham. A third genus of the family has a 



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