750 MR. D. M. S. WATSON ON 
The first account of a skull which was in any way complete 
was written by H. G. Seeley on material of Rhophalodon and 
Deuterosaurus from the Urals. Subsequently the same author 
described a good skull belonging to the South African Museum 
as Delphinognathus conocephalus. 
Except for purely systematic descriptions by Broom of four 
new genera and five new species founded on most unsatisfactory 
material, nothing further was published till, in 1909, this author 
gave a short and, as it has proved, somewhat inaccurate account 
of two skulls in the British Museum collected by Prof. Seeley. 
Subsequently Broom published a much better account of the 
type skull of Delphinognathus and brief descriptions of several 
new genera, one of which gave a complete knowledge of the 
lower jaw. 
Finally, Haughton has published a short account of a large 
skull referred, perhaps correctly, to Vapinocephalus atherstoner. 
The British Museum (Natural History) contains a large amount 
of Deinocephalian material in the form of more or less frag- 
mentary skulls and small associated sets of bones. From this it 
is possible to get some idea of the form and structure of a 
member of the group, and to give a nearly complete account of 
the morphology of the skull. 
The description of the Tapinocephaloid skull now given is 
founded on the following material :— 
I. R.1705. The type skull of Zapinocephalus atherstonei, 
represented by the right side of the occipital region up to the 
orbit, the left supraorbital region, and the anterior part of the 
face. 
Il. R. 3594. The skull already described by Broom as T'apino- 
cephalus atherstonet which really belongs to a new genus (Pl. IV. 
and text-figs. 1-4). 
This skull has lost the basioccipital condyle and the left 
quadrate region. It is very slightly distorted by pressure but 
otherwise is very well preserved, having been completely freed 
from a most intractable matrix by Mr. R. Hall, of the British 
Museum. When Dr. Broom described it, the whole outer surface 
was covered with a thin layer of matrix which has proved to be 
readily removable, so that all the sutures of the face are clearly 
and definitely shown; most of those figured by Broom are 
wrong. 
III. R. 3596 is a specimen in the Seeley collection from 
De Cypher, Gouph, consisting of a skull (text-figs. 5-7) from 
which the face in advance of the prefrontal had fallen away 
before fossilisation, the two dentaries, with some limb-bones and 
vertebre. Although also referred by Broom to Vapinocephalus, 
this skull is generically distinct not only from this type but also 
from R. 3594. 
TV. 49385 is a specimen, Q of T. Bain’s collection, from Warm 
Bad, Gouph, which consists of the posterior part of the skull, 
