1877.) 58 1 ICope. 
malian epiphysis was derived. The sculpture of the surfaces is coarser 
than that to which epiphyses are attached in the Mammalia. The name 
of the genus expresses this character. 
It is altogether probable that this genus embraced terrestrial animals, 
with powerful fore- and hind-limbs subequally developed. The typical 
species is of gigantic proportions. 
DYSTROPHAUS VIEZMALA&, Cope. 
Tn the supposed sternum of this animal (which I have not seen, but 
which was sketched by Professor Newberry), a rather small, slender and 
compressed process projects from near the middle of one of the sides at right 
angles to it. Only two of the lateral processes are represented as complete. 
The longer is subspatulate ; the shorter subacuminate. The scapula pre- 
sents three complete borders, —the proximal and two lateral ; but the distal 
is not known. Without it, the length is two and one-half times the breadth. 
The point of junction of the longer (and perfect) short border with one of 
the long borders, is much thickened, terminating in a mass of bone ‘which 
is unfortunately broken, but whose section in the line of the end border is 
a wide oval. From this point, the plate thins away to the various borders. 
The greatest thickness is nearer the border which terminates in the en- 
largement described. This surface is then gently convex in transverse sec- 
tion, while the opposite one is concave toa less degree. It is thicker at the 
middle than at the anterior border in a longitudinal direction. 
The proximal extremity of the humerus is much expanded. The greater 
tuberosity is a huge crest, as prominent as the head, and separated from it 
by a marked concavity which constricts the mass connecting it with the 
head, thus forming a neck. This concavity extends about one-third the 
length of the shaft. On the opposite side of the head a similar concavity 
excavates the shaft, separating the internal from the interior ridge. The 
latter is in its middle portion as prominent as the external ridge, and ex- 
tends as far downwards. , The extensive external face of this part of the 
bone is nearly flat. 
The internal ridge descending from the head, continues into the poste- 
rior border of the interior face of the shaft. The great tuberosity continues 
into the single external ridge of the shaft, which is thus near the middle tri- 
angular in section, the base of the triangle internal. The external extremity 
of the distal end is therefore an angle, and the interna! a convex side, 
shorter than the anterior and posterior sides. A ligamentous groove marks 
the posterior border of the extremity at a point measuring one-third of its 
jength from the externai angle. The expanse of the distal extremity is not 
more than three-fourths that of the proximal. The entire bone so resem- 
bles a tibia, as to have induced me to refer it at first to that element. The 
characters of the proximal end are such as to render such identification 
highly improbable. Such reference would also require that the distal ex- 
tremity should have afore and aft direction, an arrangement incompatible 
with the tibia. ‘ 
PROC. AMER. PHILOS. SOC. XVI. 99. 3U 
