PALEONTOLOGY 



O. mantelli have likewise been recorded from the county. But this by 

 no means exhausts the list of Surrey Cretaceous sharks, the British Mu- 

 seum possessing teeth of Corax falcatus and three vertebrae of Cetorhinus 

 duponti from the chalk of Guildford. 



Passing on to the chimaeroid fishes, a tooth from the chalk of Dor- 

 king in the British Museum indicates the occurrence of Edapbodon 

 agassizi in the county. Two other types are Plethodus oblongus and P. 

 pentagon, the former represented by a skull and the latter by teeth from 

 the Dorking chalk. Among the so-called ganoid fishes, the well-known 

 Macropoma mantelli is represented in the same collection by a crushed 

 head and dorsal fin from the chalk of Dorking as well as by vertebra? 

 from Guildford. The well-known rhomboidal scales and button-like 

 teeth of Lepidotus pustulatus occur in the lower greensand of Godalming; 

 while the smaller ornamented crushing teeth of Gyrodus cretaceus have 

 been obtained from the chalk of St. Catherine's Hill and Croydon. 

 Another Cretaceous ganoid found in the county is Neorhombolepis punc- 

 tatus, of which the national collection contains scales from the lower 

 chalk of Dorking. To a family (Amiidce) now represented only by 

 Amia calva of the freshwater of North America belongs Protosphyrcena 

 ferox, a Cretaceous fish with large spear-like teeth long known under the 

 name of Saurocepbalus lanciformis ; teeth of this type have been found in 

 the chalk of Guildford. Yet another form is Tomognatbus mordax, a fish 

 with large teeth fixed to the jaws, of which skulls have been obtained at 

 Dorking. 



Among fishes of a more essentially modern type, the extinct Cre- 

 taceous family Ichthyodectidce, which includes some species of gigantic 

 dimensions, is represented in the Dorking chalk by jaws of two species 

 of the typical genus Icbtbyodectes, namely /. elegans and 7. lewesiensis. 

 To the same family belongs the fish known as Enchodus lewesiensis, of 

 which remains have been recorded from the chalk of Shalford and 

 Guildford. An allied type is Prionolepis angustus, typically from the 

 chalk of Sussex, but also represented by scutes from that of Dorking. 

 To another family the Elopidce belongs Osmeroides lewesiensis, likewise 

 a Sussex Cretaceous fish, of which remains occur both at Shalford and 

 Guildford. Another Sussex type is Aulolepis typus, of which certain re- 

 mains have been found in the Dorking chalk. 



Neither are the so-called barracudas wanting from the Cretaceous 

 beds of the county, scales of an extinct generic type termed Cladocyclus 

 lewesiensis occurring in the chalk of Dorking as well as in that of Sussex. 

 The perch-like fishes, which only date from the Cretaceous epoch, have 

 at least three representatives in the county, one of which (Hoplopteryx 

 lewesiensis^ belongs to an extinct, while the other two (Eeryx radians 

 and B. microcephalus] are assigned to a still living genus. Of the first- 

 named remains have been obtained at Guildford, of the second at Dor- 

 king, and of the third at Reigate. 



The Lower Tertiary deposits of Surrey appear to be poor in fish- 

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