A HISTORY OF SUFFOLK 



specimens. Numerous dermal plates from the Coralline Crag of Orford 

 and Gedgrave, as well as from the nodule bed of the Red Crag, are 

 indistinguishable from those of the living thornback skate {Raia clavata), 

 while a single tooth from the Coralline Crag of Gedgrave has been 

 assigned to the common skate {R. batis). Other dermal plates, from the 

 Red Crag at Boyton and the Coralline Crag at Gedgrave, are regarded 

 by Mr. Newton as indicating a third (perhaps generically distinct) kind 

 of ray. Finally, a small tooth in the British Museum from the nodule 

 bed of the Red Crag of the county indicates a species of monk-fish 

 [Squatind). A second tooth of similar type has been obtained at Little 

 Bealings, and there is a third in the Museum at York, also from the 

 Red Crag. 



Allusion has already been made to the ' derived ' vertebrate fossils of 

 Suffolk, or those which are definitely known to have been washed out 

 of older formations. These may now be mentioned somewhat more 

 fully. In 1856 Sir R. Owen' described a mammalian tooth from the 

 Red Crag of the county, which he regarded as referable to that primitive 

 group of Carnivora of which the Eocene genera Pterodon and Hycenodon 

 are well known representatives. Although the specimen cannot now be 

 found it is probable that the determination is correct, and that the tooth 

 originally came from the London Clay. That formation is certainly the 

 horizon whence was derived part of a skull of the Eocene mammal 

 Hyracotherium leporinum obtained from the Red Crag of the county and 

 described by Sir R. Owen.^ The genus and species in question, it may 

 be observed, were first described from the London Clay of Kent, and 

 form one of the ancestral types of the horse line. Teeth of a much 

 larger size from the Red Crag of the county, some of which are pre- 

 served in the Museum at Ipswich and others in the Museum of Practical 

 Geology, belong to Coryphodon eocanus, another primitive odd-toed 

 mammal typically from the London Clay of Essex. An imperfect skull 

 in the Museum of the Royal College of Surgeons, said to be from the 

 Red Crag of the county, has been described by Sir W. H. Flower,' and 

 provisionally assigned to the genus Xiphodon, under the name of X. platy- 

 ceps, of which it forms the type. As the teeth are wanting the genus 

 to which this curious specimen belongs cannot be definitely determined. 

 Mr. Newton observes that although its exact age is uncertain, yet it 

 approximates most nearly in general appearance to the so-called box- 

 stones of the Suffolk Crag. 



The only reptilian remains recorded from the Crag of the county 

 appear to be the skulls of turtles, which have evidently been washed out 

 of the London Clay, and doubtless belong to the forms characteristic of 

 that deposit, such as species of Argillochelys and Lytoloma. 



Fish palates and teeth, likewise mainly of Lower Eocene types, are 

 far from uncommon in the nodule bed of the Red Crag. Among them 



' ^imrt. Jcurn. Geol. Sk. xii. 227. * Geol. Mag. (i) ii. 339. 



' Proc. Zool. Sx. 1876, p. 3. 



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