286 THE EOCENE FLORA AND FAUNA.
Otodus obliquus is represented by a very characteristic tooth.
Odontaspis macrota. I have an example of the typical lateral
teeth of this species, identical in shape with Fig. 20 in Mr.
Woodward's paper above referred to. This is of special interest
as he remarks that "it is still uncertain whether this species
occurs in the London Clay."
Odontaspis cuspidata was not common.
Odontaspis elegans, as restricted by Mr. Woodward, was by
far the most abundant of the shark's teeth. I obtained over
sixty during a couple of hours' search one afternoon. This haul,
however, was never repeated ; I had evidently come across the
accumulation of years.
Besides the teeth of Oxyrhina hastalis* (Ag.), and the dermal
spines of Rata clavata* (L.), which are probably of Pliocene
age, the Walton Crag contains a number of other derived
Selachian remains which have clearly been washed out of Eocene
strata, usually London Clay, as shown by the hardened and
phosphatized nodules of that material which often partially
encloses them. They are :—
Galeus sp.
*Odontaspis elegans or O. cuspidata
*Odontaspis macrota
*Myliobatis toliapicus
The tooth of Galeus is unfortunately lost. I remember very well
comparing it with the specimen from the London Clay in the
British Museum (A. S. Woodward's fig. 28, op. cit.) with which
it was identical. The specimen of Odontaspis macrota is the twin
brother of the one recorded above from the London Clay, that is
with regard to shape, for it is stained a reddish colour through
long contact with its ferruginous matrix. Myliobatis toliapicus is
represented by numerous pieces of its peculiar dentition.
In conclusion I would point out that the following list
might be considerably enlarged by further search in this promis-
ing locality.