HALCYORNIS TOLTAPICUS. 555 
part of the skull of the smaller species of Gull; but the 
absence of the frontal chevron-shaped ridge, defining the 
excavation (fig. 234, c, 0) for the supra-orbital glands, 
which ridge is present in all the species of Larus, as it is 
in most other long-winged marine birds, forbids a refe- 
rence of the fossil to that genus. The occiput is also rela- 
tively broader in the fossil (fig. 234, 4). 
In the general form of the cranium, I have hitherto 
found the nearest resemblance to the fossil in the King- 
fisher (ib. p and ©); but the temporal fosse (#) extend 
further upon the upper surface of the skull. In the sub- 
joined cut (fig. 235), I have restored the skull after the 
pattern of that of the Kingfisher, in order to render the 
fossil more intelligible. 
Fig. 235. 
Fossil cranium of Bird, eocene clay, Sheppey. Nat. size. 
