PALAEONTOLOGY 



I 



'finds' made some years ago by Mr. H. M. Klaassen in 

 the Lower Eocene Woolwich and Reading beds of the Park 

 Hill railway cutting at Croydon constitute the chief point of 

 interest in the palaeontological history of the county, so far as 

 vertebrates are concerned. The first of these ' finds ' is one of the 

 bones (ulna) of the fore-limb of a large primitive type of hoofed mam- 

 mal referable to a genus first described by Sir R. Owen from the London 

 clay of Essex under the name of Corypbodon, in allusion to the ridges 

 capping the crowns of the molar teeth. By Mr. E. T. Newton, who 

 described it, 1 the Croydon fossil is regarded as indicating a species dis- 

 tinct from the one to which the Essex remains belongs, and it was ac- 

 cordingly named Corypbodon croydonensis. 



The second peculiar form is a gigantic flightless bird, considerably 

 superior in size to the ostrich ; it is represented by two imperfect bones 

 of the leg, likewise obtained from the Park Hill railway cutting. These 

 bones were also described by Mr. Newton, 3 who named the bird to 

 which they belong Gastornis klaasseni, after the finder of the specimens. 

 The genus Gastornis, it may be mentioned, was first established on the 

 evidence of bones from Lower Eocene deposits at Bas-Meudon, in France, 

 and was subsequently discovered at Rheims. Mr. Newton regards the 

 English bones as indicating a species distinct from the one represented by 

 the Meudon specimens. Whether Gastornis belongs to the same group 

 of birds as the ostrich may perhaps be doubtful, as it is now ascertained 

 that representatives of other groups have acquired a large bodily size 

 concomitantly with the loss of flight. The limb-bones present a con- 

 siderable resemblance in certain respects to those of the duck tribe. 



Corypbodon croydonensis and Gastornis klaasseni, together with the 

 undermentioned Icbtbyodectes e/egans, appear the only extinct vertebrates 

 peculiar to the county. 



The Surrey chalk has yielded remains of at least two species of 

 reptiles and several kinds of fishes, and doubtless more remain to be dis- 

 covered. The first reptile is Polyptychodon interruptus, of which remains 

 from the chalk of the county were described by Sir Richard Owen. 3 This 

 reptile was a swimming marine creature allied to the plesiosaurs of the 

 Lias, but with a much shorter neck and larger head. In these respects 

 it resembles the pliosaurs of the Jurassic strata, from which it differs by 



1 Proceedings of Geologists' Association, vol. viii. p. 254 (1883). 

 8 Trans. Zoo/. Sec. London, vol. xii. p. 143 (1866). 

 3 Quart. Journ. Geol. Soc., vol. xvi. p. 262 (1860). 



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