84 Reviews—Dr. van Hoepen—Stegocephalia, Senekal. 
Williston and Dr. Broom, was known, the reviewer was puzzled by 
certain appearances which it is now clear are probably to be explained 
by the presence of a post-splenial and a precoronoid. The reviewer 
now knows that a post-splenial is present in ‘ Bothriceps’ hualeyz, 
and that the large bone interpreted by him as the coronoid in 
Micropholis is really the same bone. It probably occurs also in 
Batrachiderpeton and ‘ Loxomma’, though the evidence here is not 
yet clear. The vertebral column is similar to that of Zryops, and the 
tail is fairly long. 
The shoulder-girdle has widely expanded clavicles and interclavicle, 
as in the large Triassic forms and in the small Permian Zrimerorachis 
and ‘ Bothriceps’ huwleyi. There is a cleithrum, which, as shown in 
the useful text-figure, caps the scapula as it does in Hryops. The 
scapulo-coracoid is structurally similar to that of Hryops, but the 
scapular portion is far shorter and makes a much more pronounced 
angle with the coracoidal end. The reviewer remembers seeing 
a suture between the precoracoid and the coracoid, and may perhaps 
mention here that he owes to the generosity of Professor Case 
a young scapula of an Eryopid which shows that the precoracoid was 
a separate bone forming part of the glenoid cavity, just as in 
Deinetrodon. The glenoid cavity has the peculiar screw shape 
common to primitive reptilia and Stegocephalia. 
The bones of the fore-limbs are generally similar to those of 
Eryops, but the author inclines to the belief that the humerus was 
much less twisted. The humerus of Mastodonsaurus, though other- 
wise similar to that of Hryops, is less twisted and may have resembled 
that of Dyriodon. 
There are stated to be only two ossified carpals and only four 
metacarpals; as this is a point of very great importance, and as 
Eryops and Cacops seem to have five fingers, it is desirable that 
a definite statement of the evidence should be published. 
The pelvis is generally similar to that of Hryops, the relation of 
the ilium to the sacral rib being the same in both: it is, however, 
perhaps still more similar to that of Mastodonsaurus when stripped of 
the addition of an ischium and a scapulo-coracoid with which it is 
provided in the familiar restoration. 
The hind-limb is similar to that of Hryops, so far as the latter is 
known, but it is very unfortunate that Dr. van Hoepen has not 
published a figure of the well-ossified and extremely interesting 
tarsus with five or six tarsals of which he gives a description. 
The reviewer some time ago suggested that the large Triassic 
Labyrinthodonts were derived from large Permian rachitomous forms, 
and these from the large Embolomerous amphibia of the Coal- 
measures; all subsequent work, both by other authors and by the 
writer, has tended to support this view: in particular the very 
interesting demonstration by Professor Williston that Zrimerorachis, 
which had been generally supposed to he the most primitive of the 
Texas amphibia, is really a specialized secondarily aquatic type, 
has removed a stumbling-block and added an important new idea. 
The writer regards Eryops as on the whole a neutral and perhaps in 
some ways a conservative animal. 
