178 DR. R. BROOM ON THE [| Feb. 17, 
consists of two complete mandibles in articulation with the 
posterior half of the skull. The lower jaw lies almost at right 
angles to the axis of the skull, and the upper cervical vertebrae 
have been to some extent protected by passing down between the 
two rami. The skull consists of the practically complete occiput 
with both temporal arches in almost perfect condition, and with 
most of the parietal and sphenoidal regions well shown. Though 
the sutures unfortunately are not distinct, the occiput is so well 
preserved, practically without distortion, that I think it worthy 
of being figured. 
The vertebrze so far as preserved consist of the proatlas, atlas, 
axis, and the 3rd and 4th cervical vertebre. 
The atlas (a¢.) consists of a well-developed arch and a distinct 
hypapophysis (A.at.). The arch is partly broken in the middle, but 
must have borne considerable resemblance to that of the mammals. 
It differs in having had a distinct posterior zygapophysis (z.at.) 
for articulation with the small anterior zygapophysis of the axis 
z.ax.). The zygapophysis of the left side is well preserved, but 
that of the right has been broken off. On the right side the 
outer part of the arch is continued backwards as a well-developed 
bony process or rib (7.a¢.). It is probable that the process is 
really a rib, but I have been unable to find a suture between it 
and the arch. On the under surface, what appears to be part of 
the rib of the left side is seen lying by the side of the body of the 
axis (7.at.). The well-developed hypapophysis is also well seen. 
It appears to have had only a ligamentous connection with the 
arch of the atlas. 
In front of the arch of the atlas, and lying in the hollows formed 
above and outside of the occipital condyles, are the two portions 
of the proatlas. Each consists of a short bony arch with a 
well-developed process passmg upward and outward from its 
outer end. e 
The axis is well developed, and bears considerable resemblance to 
that of Cynognathus. The spine forms a very large flattened crest. 
In the specimen it is somewhat damaged, but there is probably 
not a great deal missing. In front, the spine passes forwards 
over the arch of the atlas, and possibly forms an articulation 
withit as in the Monotremes. Between the anterior part of the 
spine and the odontoid process is the small anterior zygapophysis 
(z.ax.). The odontoid process (0.p.) is well developed, and on the 
right side it is seen articulating with the arch of the atlas. On 
the under surface the body of the axis is seen, asalso a part of the 
odontoid process in articulation with the hypophysis of the atlas. 
On the upper surface, near the posterior end of the centrum, on 
the right side is a portion of the rib of the axis. 
The 3rd and 4th cervicals present no features worthy of any 
special remark. Remains of ribs are seen in connection with 
each. 
In the type specimen of Zrirachodon kannemeyert there are 
preserved and well shown the two portions of the proatlas, the 
