Page:VCH Suffolk 1.djvu/81

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PALAEONTOLOGY are specimens of the dentition of the extinct genus Phyllodus, referable to the three species P. speciosus, P. hexago?ius and P. toliapicus. A frag- ment of a fin-spine from Foxhall is referred by Mr. E. T. Newton to the extinct cat-fish Arius egertoni, whose typical horizon is the Middle Eocene of Sussex. Of the pycnodont ganoids, or those with rounded or oval crushing teeth, specimens from the Crag have been assigned to the genera Pycnodus, Gyrodus, Pisodus and Lepidotus ; those belonging to the first and third being probably derived from the London Clay and the others from still older formations. Dental plates' of fishes allied to the living chimasra or king-of-the-herrings are also met with in the Red Crag, and have been assigned to the Eocene genera Edaphodon and Elasmodus. To the same group belongs a fragment of a fish-spine from Woodbridge, now in the British Museum, which has been referred to the Eocene Ccelorhynchus rectus. Allusion to ' derived ' teeth of sharks belonging to the genus Odontaspis has been made in an earlier paragraph. In addition to these occur larger teeth belonging to the Eocene shark known as Otodus obli- qiius. The large roller-like dental plates of eagle-rays of the genus Myliobatis, occasionally met with in the Red Crag, have for the most part been identified with the Eocene species M. dixoni and M. toliapica. Others belong to the allied genus /Etobatis. The Ipswich Museum possesses a few fragments of the well known crushing teeth of the Cretaceous genus Ptychodus, which have been identified with P. polygyrus, so abundant in the English Chalk. Lastly, fragments of teeth from Woodbridge indicate a saw-fish [Pristis), doubtless identical with a lower Eocene species. Of far more interest than the above derived specimens are certain fossils obtained in the year 1839 by the late Mr. W. Colchester of Ipswich in the Lower Eocene sand of Kingston near Woodbridge, some of which are described in Owen's British Fossil Mammals and Birds. Among these a fragment of a lower jaw, showing one entire cheek tooth, has been referred to an opossum with the name Didelphys (?) colchesteri ; but the real affinities of the specimen must remain undecided. Another mammal, typified by two cheek teeth of the upper jaw, was named by Owen Hyracotherium cuniculus, as these teeth, although smaller, appeared generically identical with those of H. leporinum. A fragment of the lower jaw, with two teeth, of the former species included among Mr. Colchester's collection was at first regarded as indicating a monkey, and accordingly named Macacus eoccenus. Another mammalian tooth from Kingston is figured by Owen (op. cit. p. 17), and provisionally regarded as that of some kind of bat. A fragment of a jaw from Kingston described by Sir R. Owen as Lacerta (?) eocana, appears to be certainly reptilian, although its precise generic determination is probably impossible. Certain fish-scales from Kingston presented to the British Museum by the Rev. J. Middleton in 1854, are referred by Dr. Smith Woodward to the genus Lepidosteus, now represented by the bony pike of the rivers of North America. From 45