110 Proceedings of the Royal Society 
Grangemouth specimens. These differences are, I believe, merely 
individual and not specific. On the other hand, there is so close a 
correspondence in the general form of the lower jaws, in the num- 
ber and cuspidation of the teeth, and in the mode in which they 
are implanted in their sockets, that I am of opinion these seals 
were animals of the same species. This identity in the specific 
characters of the seals found in the clay formations on the east 
coast of Scotland furnishes an additional argument in favour of 
the view, that they have been deposited at the same epoch and 
under the same conditions. We may now inquire if this clay 
seal corresponds with the present British species, the Gallocephalus 
vitulinus. 
Inner surface of the right half of the lower jaw of the Grangemouth seal, 
the size of nature. The outline of the coronoid process is filled in from 
the Portobello seal. The single tooth is one of the upper molar series. 
Dr Knox stated that the Camelon seal was identical with the 
species now inhabiting the Forth, and many other naturalists who 
have written on this matter are inclined to the same view. At 
the time when Dr Knox wrote, the specific differences between the 
various northern seals had not been precisely made out, and the 
determination is even yet one of much difficulty, unless the skulls 
and teeth can be compared with each other. Dr Knox does not say 
what the bones were which came under his observation, so that we 
have now no means of knowing how far he had in his possession 
the materials for making an exact comparison. 
