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is broad and so deep as to pass below the spine. The spine is so 
slanted that what is called the upper surface of the acromion looks 
almost directly outward. It is moreover very slight. The supra- 
spinous fossa is rudimentary. Its anterior portion is wanting and 
most of the posterior part of the floor is convex instead of concave. 
Dr. Jackson had perfectly recognized that the bones of the forearm 
were two ulnae, and that there was no radius; but the parts about 
the elbow were so hidden by the dried muscles that very important 
features could not be made out. I therefore had the specimen photo- 
graphed before it was disturbed and rewrote the description of the 
soft parts. Then softening the dried muscles by a steam of almost 
boiling water I examined thoroughly the bones at the elbow and 
finally separated the arm from the forearm. The bones were then 
photographed. The wrist and hand were not further dissected as the 
preparation gave a good view of the dorsal aspect of the carpal bones. 
The Bones. The forearm consists of the normal left ulna and 
of a right one in the place of the radius. The left one shows little 
that calls for comment, excepting that there is a projection outward 
at the place of the lesser sigmoid cavity to join a corresponding pro- 
jection from the other ulna. The upper surface of this projection 
articulates with the humerus. At the lower end the styloid process 
is less prominent than usual, and the head rather broad. The right 
or extra ulna is put on hind side before, that is the back of the 
olecranon projects forward over the front and outer aspect of the 
humerus. If the reader will place his right forearm on the outer 
side of the left one he will see that it is necessary for the ulna to 
be thus inverted if the thumbs are to touch and the palms to be 
continuous. This olecranon is thinner, flatter, and longer than normal. 
The coronoid process is rudimentary. From the side of this process 
and from the shaft just behind it arises the projection already referred 
to which meets a similar one from the normal ulna (fig. 2). On the 
front of this there is a small articular surface looking forward which 
suggests a part of the convexity of the head of the radius. These 
projections which touch each other are held together by a strong 
interosseous ligament. The lower end of this ulna is very like the 
other only somewhat broader. 
The upper end of the humerus, concealed as it is by dried 
muscles, presents nothing noteworthy. There is no roughness for the 
attachment of the deltoid though the place for it is exposed. At the 
lower end the internal condyle is normal. It is quite unmistakable 
and is the most evident starting point. On the posterior surface is 
