206 PROF. W. K. PARKER ON THE STRUCTURE AND 
B. The Endocranium of the adult Newt. 
The hinder and middle skull are thoroughly ossified ; the fore part or nasal region 
is soft. 
The two sides over the foramen magnum (fig. 4, f m) are separated by a very narrow 
tract of cartilage; this part and the crescentic internasal band (¢.n. ¢) are all that keep 
the two sides conjoined. 
The reason of this is that the greater part of the second basicranial bands (para- 
chordals) have been absorbed, and not only these later, but also much of the earlier 
bands; for the whole of the posterior or parachordal part of the trabecula (¢r) has been 
absorbed also. 
Hence there are now only two Jones on each side, namely the occipito-auditory mass 
and the sphenethmoid (sp.e), the latter running along the whole extent of the orbital 
region, and only separated from the former by a small cartilaginous wedge (fig. 4, #7). 
Thus the shallow sella turcica and the faint and almost aborted bony cephalostyle are 
now to be seen on the upper surface of the parasphenoid, the superficial “‘ succedaneum ” 
of the proper basis cranii. 
The foramen magnum (/f. m) is very large and obliquely supero-posterior; the arch 
over it narrows so as to have a very small keystone part of cartilage; at the base there 
is a wide semicircular emargination for the “ odontoid rudiment.” 
The occipital condyles (0c. ¢) are obliquely inturned, subpedunculate, reniform, and 
postero-inferior ; the arch itself is narrow, the posterior canal (p. s.c) running very near 
to the foramen magnum. 
The three canals (a. s.¢, p. 8. ¢, p. 8. ¢) are large and protuberant, the tegmen tympani 
(é. ty) scarcely overhanging the horizontal canal. 
Cartilage is seen in two places besides the condyles; but only one of these parts 
belongs to the capsules; this is the stapes (st), which is oval, thick, and almost 
transversely placed. 
The third part of cartilage belongs, like the condylar part, to the basal plate; this is 
the basipterygoid facet (fig. 6, d.py), to which the bulbous pedicle (pd ) is articulated. 
The facial nerve (vi1) escapes on the inner side of this joint, the ninth and tenth (1x, x) 
pass out behind the opisthotic edge of the fenestra ovalis (st, vb). The vestibule in front 
of that opening forms a very elegant crescentic swelling, as much marked as the curved 
risings on the upper face of the capsule. 
The trigeminal nerve (fig. 3, v) escapes at a part of the skull where cartilage still 
lingers, dividing the prootic from the sphenethmoid; the optic nerve (I) escapes 
through a smallish passage in the hinder fourth of the latter bone. 
A small anteorbital tract of cartilage in the trabecular wall is seen close behind the 
perforated prefrontal (sp.e, pf); the orbitonasal passes through the perforation in 
the prefrontal. The nasal roofs (fig. 4, 2a) are nearly as large as the auditory capsules ; 
they are broadly crescentic in form, being deeply notched outside. In this notch the 
nostrils (e.”) lie; they are wide apart, but not so wide apart as the inner openings 
