J38 
TEliTJARY YERTEBRATA OF THE FAYtiM. 
succession. The difFereiices between the palatines and pterygoids in the earlier and 
later ty])es are of course dependent on the same causes. 
d’he anterior portion of the skull, particularly the upper portion, is completely 
wanting in the large specimen on which the above description is for the most part 
founded ; but another specimen (PI. XIII.) supplies the necessary information 
concerning this region. It is the anterior ])ortion of a skull of a very young 
individual in which the milk-teeth are still in use ; it includes the whole of the 
frontals as far back as considerably behind the postorbital processes, the nasals, 
])rcmaxillaries, lachrymals, and most of the maxillae, including the zygomatic 
process, also the palate as far back as the level of the middle of the zygoma. 
There are two teeth in situ on one side and three on the other ; they are probably 
mm. 2, 3, 4, and will be described below. The crushed base of one of the milk- 
tusks is ]n-eserved in the socket. As will be shown below, this specimen in the 
shortening of the nasals and the shifting backwards of the narial opening supplies 
a beautiful illustration of the approximation towards the later Proboscidean type found 
in this genus. In the relations of the bones to one another it precisely resembles 
The right frontal {fr.) is mostly broken away, but the left is better preserved, and 
although its actual junction with the parietal cannot be observed, nevertheless 
little can be wanting from its hinder border. Together the upper part of the 
combined frontals in the interorbital and part of the postorbital regions forms the 
gently convex skull-roof. In this young specimen scarcely any trace of the supra- 
temporal ridges (the divided sagittal crest) can be seen, but it is evident that they 
ran on to the postorbital processes. External to these ridges in the postorbital 
region the frontals run down into the temporal fossm, and are strongly convex from 
above downwards. The postorbital processes are blunt prominences, from each 
of which a ridge runs downwards and backwards, separating the orbit from the 
temporal fossa. Ventrally this ridge must have been continuous with that formed 
by the free edge of the alispheuoid described above. In front of the postorbital 
processes the frontals form a well-defined upper rim to the orbit, and anteriorly 
they unite in suture with the maxilhu, lachrymals, prcmaxilhe, and nasals, their 
general relationships to the neighbouring bones being exactly as in Elephas. 
The lachrymal {lac.) is a small bone wedged between the frontal and maxilla, 
and grooved below by the upper surface of the antorbital canal. It is ])erforated 
by a large foramen which lies within the border of the orbit ; above the foramen 
and on the rim of the orbit there is a small but prominent tubercle. 
The nasals [na.) are short bones which already approximate very nearly in form to 
those of Elephas. Together they ])roject in a blunt point over the nasal aperture. 
Eostc'riorly they are together roughly semicircular in outline and mute for the greater 
part of their width with the frontals, but externally to these with the premaxilla'. 
