340 
the skull of Polypterus to that of Urodeles is unmista- 
keable. ‘The most apparent differences are first the inclusion of 
vertebral elements in it, and second the presence of an ossified ecteth- 
moid with which articulates the autopalatine. 
3) Palatine region. The anterior part of the parasphenoid where 
it appears on the palate is spoonshaped and bears teeth. Beyond 
the tooth bearing part the bone continues as a spicule underlying the 
nasal septum. Beneath this anterior prolongation is a small bone 
formed by the fusion of the bases of from 4—8 teeth and this corre- 
sponds to the Vomer of Teleostei at an early stage of the develop- 
ment of the latter — that is before it shows the secondary palatal 
prolongation along the under surface of the parasphenoid. What has, 
therefore, been called the “paired vomer” is really “dermopalatine”. 
Furthermore traces of the true vomer have been recorded in Crypto- 
branchus!) and the socalled vomer of Amphibia so evidently corresponds 
with the dermopalatine of Polypterus that the two must be homo- 
logous. 
The bone termed metapterygoid is purely a cement or dermal bone. 
There is no metapterygoid preformed in cartilage. 
4) Muscles. The jaw muscles do not correspond to the fish type. 
A masseter, pterygoid and temporal, the last named showing traces 
of a division into an upper and lower portion, are present and con- 
form very closely to the Urodelan type. Judging from its innervation, 
the retractor hyomandibularis corresponds to the digastric of Urodeles. 
An intermaxillaris anterior and posterior are present attached and 
disposed as in Urodeles. In my final work I shall describe the nerves 
and show their homologies. 
5) Cranial nerves. The cranial nerves have been described at 
some length by van WısHE with whose determinations the following 
account is in accord. From the acustico-auditory ganglion a stout 
nerve runs forward and upward under the anterior semicircular canal 
and above the jugular vein. Before emerging from the skull it shows 
a ganglionic swelling. This ganglion receives a commissure from the 
Gasserian ganglion, and then from it pass forward first 3 small bran- 
ches (fig. 1, a, 6, c) which supply the mucous canals in the squamosal 
and postorbital regions, secondly the Ramus ophthalmicus superficialis 
and thirdly the Ramus buccalis. A short distance beyond its origin 
the Buccalis gives off a branch (fig. 1 d), to the mucous canal in the 
hinder part of the maxilla, 
1) I have as yet no personal observations to record, 
