100 
BRITISH ASSOCIATION.- 1835. 
his observations to the instances of deficient and perverted develop¬ 
ment. 
It appeared that the head was not deformed, but the brain was 
small, and the cranium pretematurally thick, particularly in the 
frontal region. A very considerable portion of the right hemisphere 
of the brain was deficient, and its place occupied by a large cyst 
containing limpid serum. There was also a remarkable deficiency 
of development in other parts of the cerebral mass at this side. The 
optic thalamus, corpus striatum, right pair of the tubercula quaari- 
gemina, crus cerebri, and corpus pyramidale were all less developed 
than the corresponding parts of the opposite side. The optic and 
other nerves were normal, as were also the arteries at the base of the 
brain. The total absence of convolutions and of the grey substance 
of the brain in the situation of the cvst, the deficient develonment 
of the other parts enumerated, the healthy consistence and appear¬ 
ance of the cerebral mass and its membranes elsewhere, together 
with the history of the case, seemed to indicate that the phsenomena 
were the result of original conformation, and not of any subsequent 
morbid action. 
The left inferior extremity presented all the external characters of 
an accidental dislocation of the thigh upwards and outwards; but it 
appeared from an examination after death, as well as from the history 
of the individual, that the dislocation must have been congenital. 
The acetabulum was imperfectly formed, and not adapted to con¬ 
tain the head of the femur. This bone was also of abnormal form. 
The axis of the head and neck fell directly on the anterior instead 
of on the internal surface of the shaft, as if the bone had been 
twisted; the head of the femur was smaller and less spherical than 
usual, and the bone was in some degree atrophied. The ligaments 
were of healthy structure, and retained their usual connexions, but 
seemed to have been gradually elongated so as to allow the head of 
the bone to rest on the dorsum ilii. There was no cavity formed 
here, but some strong ligamentous bands connected the cajDsule, 
where it invested the head of the femur, with the surface of the 
ilium. The interarticular ligament was of a broad taper-like form 
and much elongated; the cotyloid formed a flat moulding round the 
acetabulum. The muscles were healthv in structure, but in some 
degree atrophied, and the direction of their fibres was changed ac¬ 
cording to the altered relative situation of their usual lines and 
points of origin and insertion. 
There was no trace whatever of previous violent injury or of dis¬ 
ease of any of the structures in or around the articulation. 
The left arm was flexed, atrophied, and nearly useless; the hand 
was extremely pronated. The flexed state of the limb seemed to 
depend on the contracted state of the muscles; the pronation of the 
hand or the circumstance of the inferior cubito-radial articulating 
surface of the ulna presenting inwards, instead of outwards and for¬ 
wards, and the radius being accommodated to it. 
The subject of these observations seemed to have very few ideas, 
and these were of the most simple kind, principally connected with 
