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the form of its proximal articular surface is shown at fig. 3, 111.1. A rough, somewhat 
prominent tract, of a triangular shape, extends from the lower angles of the proximal 
surface forwards upon the lateral and under surface of the shaft, over more than one- 
third of its extent; and they bound a shallow channel which impresses the middle of 
the under surface of that part of the bone. ‘The section of the middle of the shaft of 
this phalanx yields a full transverse ellipse, a little flattened at the under part. The 
upper surface of the phalanx is almost straight lengthwise: there is a slight depression 
aboye the upper border of the distal trochlea. This trochlea is more equally divided, 
and by a less deep median groove, into the two articular convexities, than in the pha- 
lanx 11. 1: there is a depression at the middle of the under border of the surface, and 
a deep and large ligamentous depression on each side of the distal trochlea, The 
second phalanx, 111. 2, differs from 11. 2, not only by its greater size, but by its more 
symmetrical form, and by the straight line in which the upper surface extends from 
the posterior to the anterior trochlea. The inner of the two divisions of the proximal 
trochlea is rather the largest, but the inequality is less than in 11. 2. The distal trochlea 
is almost symmetrical; the under surface is more deeply notched than in 1. 2; the 
outer of the two impressions for the lateral hgament is the deepest. 
The third phalanx, 111, 3, has almost a square contour, with three of the sides slightly 
concave, and the fourth formed by the proximal articular surface slightly produced at 
the middle: the section of the middle of this phalanx would be nearly a semicircle, the 
under surface being flat transversely : the pits for the lateral ligaments, near the distal 
end of the bone, are large and well-marked: the median depression of the distal trochlea 
is shallower than in 11, 2, The proximal surface of the ungual phalanx is consequently 
marked by a much more feeble median vertical prominence, and it is broader and of a 
more symmetrical form than that of the ungual phalanx of the inner toe (11. 3); it is 
very little longer than that phalanx, and in other respects closely resembles it. 
The proximal phalanx of the outer toe (rv, 1) is characterized by its unsymmetrical 
proximal surface and its great breadth in proportion to its length. The proximal arti- 
cular surface is less expanded in proportion to the shaft than ini. 1. The median con- 
cavity of that surface is smaller in proportion to its peripheral convexity: the inner 
moiety of the surface has a much greater vertical extent than the outer one, its lower 
angle being produced downwards and backwards, as shown in fig. 3: a deep notch di- 
vides it from the corresponding part of the outer surface ; a broad rough tract extends 
forwards from the lower half of the outer surface along half the extent of the shaft : the 
similar rough tract from the lower angle of the inner part of the proximal articulation 
is narrower and of less extent. The smooth under surface of the shaft is slightly concave ; 
the upper surface is slightly concave lengthwise, convex transversely, The distal tro- 
chlea is divided by a deeper median vertical groove than in ru. 1, and the inner con- 
vexity is broader, whilst the outer one is the most prominent: the inferior boundary of 
the distal trochlea is sharply defined and almost straight, not notched in the middle as 


