RARE LUSUS NATURAE. 
324 
the other nine inches. An incision having been made 
longitudinally from before backwards on the under surface, 
it was found that a small peritoneal sac, of about two ounces 
capacity, existed in front of the brim of the pelvis. All the 
muscles were in a state of fatty degeneration; their nerves 
had disappeared or never been present. The inferior ex¬ 
tremity of the femur has normal condyles, but only a single 
non-articular, prominent ridge. There is no patella; upper 
extremity of the femur very small, firmly bound into the 
acetabulum by the remains of the muscles. Pubis, ischium, 
and lower part of ilium well formed, but proportioned in 
size to the upper extremity of the femur. Crista, spinous 
processes, and superior third of ventral surfaces of ilia united 
together by a very firm, fibro-cartilaginous union, the an¬ 
terior part of which forms a flat and rounded prominence of 
about the size of a florin, while from the posterior an inde¬ 
finite fibrous band passes a short way backwards, affording 
attachment to the imperfectly-formed sacro-sciatic ligaments. 
The pelvis, as formed by these ossa innominata, is fairly 
wide posteriorly, but anteriorly presents an inlet of about 
three inches from above downwards, and not half an inch 
wide. The viscera consist of a sac extending inwards for 
a little more than an inch from the urino-generative aperture ; 
from it a muscular band, representing the bladder, extends 
to the umbilicus, where it forms the urachus, which, with 
the umbilical artery and vein, extended into the umbilical 
cord. On the floor of the aperture, about half an inch in, 
are two small openings terminating in closed extremities. 
The umbilical, femoral, and two vesicular arteries meet at a 
large triangular dilatation, the walls of which seemed rather 
red. This was situated at about an inch above the umbilicus. 
Further careful dissection showed the remnants of the uterus 
and ovary situated above the bladder, and partially sur¬ 
rounded by peritoneum. The veins corresponded in every 
respect to the arteries. 
In this remarkable specimen we see the following defects 
of formation :—The epiblast , it may seem, did not become 
unfolded to produce a cerebro-spinal nervous centrum ; it 
simply produced a well-formed cuticle, investing the hind 
limbs and the central mass. The hypoblast developed only 
at its extreme posterior part, where it, however, is only doubt¬ 
fully present, as the lining of the urino-genital aperture may 
have been derived from the epiblast. The mesoblast seems to 
have undergone development, in so far as the state of the 
other layers would allow it, to have produced bones, 
muscles, blood-vessels, and probably nerves, and also, in so 
