204 
There is no trace of the attachment of a hallux. 
Of the three trochlez (Z MK) the median (J/) is conspicuously 
the largest, the external (4) the next in size, and the internal (Z) 
the smallest. The width proportions being, in a bone 13? inches 
long, 43 mm., 31 mm., and 14 mm. respectively. Their promi- 
nence anteriorly, and production inferiorly, are in the same order, 
though it is only the meso-trochlea which is produced, and that 
to a slight degree, beyond the plane of the anterior surface 
of the shaft. Posteriorly all three trochlez are produced to about 
the same level and to the extent of little more than half an inch 
beyond the plane of the posterior surface of the shaft immediately 
above them. 
The meso-trochlea is widest about the level of the tip of the 
ento-trochlea, the width, however, diminishing considerably from 
this point both as its surface extends upwards and backwards. 
The articular surface of this segment bears a well-marked vertical 
groove, plainly represented in figs. 1, 2, and 4, extending from its 
commencement to its termination ; its lateral surfaces, especially 
that on the outer side, are Pee Of the ecto-trochlea the 
anterior surface slopes backwards as it extends outwards, and 
bears a very slightly marked shallow groove, barely observable 
in the figures. Like the meso-trochlea, it diminishes in width 
from the commencement to the termination of its articular sur- 
face ; its inner surface is concave, and on its outer surface is a 
subcircular depression. The small ento-trochlea preserves nearly 
the same width throughout its contour; its surface is convex 
transversely ; its outer aspect is somewhat concave, and on its 
inner is a small, shallow depression. Corresponding to the 
diminishing width, posteriorly, of the trochleze themselves the 
trochlear interspaces are wider behind than in front, and that 
between the middle and outer segment reaches to a higher level 
than its fellow. 
Just above the ecto-trochlear interspace are two foramina, 
situated vertically above one another; the lower is separated 
from the summit of the interspace merely by a bar of bone,* 
while the other perforates the whole thickness of the lower ex- 
pansion. The anterior orifices of both of these are shown in 
Pl. v., fig. 1, W..; in fig. 2 the posterior orifice of the upper one 
only is visible (VV). The shallow groove, described as existing on 
the lower part of the front surface of the shaft, leads towards the 
upper of these foramina. In one specimen, only, a similar 
foramen exists between the meso- and ento-tarsus just above the 
internal trochlear interspace at a level corresponding to that of 
the upper of the two perforations on the other side. 
*In a good many specimens this bony bar which forms the lower 
boundary of the lower foramen has broken away. 
