E. THE VEINS.

These commence at the foot with a series of plexuses, which may be
described as forming (1) AN INTERNAL OR INTRA-OSSEOUS VENOUS SYSTEM, and
(2) AN EXTERNAL OR EXTRA-OSSEOUS VENOUS SYSTEM.

1. THE INTRA-OSSEOUS VENOUS SYSTEM.--This is a venous system within the
structure of, and occupying the semilunar sinus of the os pedis. It follows
in every respect the arrangement of the arteries as before described in the
same region. Efferent vessels emerge from the plantar foraminæ, follow the
plantar fissures, and ascend within the basilar processes of the os pedis.
Here they lie under shelter of the lateral cartilages, and assist in the
formation of the deep layer of the coronary plexus of the extra-osseous
system.

2. THE EXTRA-OSSEOUS VENOUS SYSTEM.--This may be regarded as a close-meshed
network enveloping the whole of the foot. Although a continuous system, it
is best described by recognising in it three distinct parts:

_(a) The Solar Plexus_.
_(b) The Podophyllous Plexus_.
_(c) The Coronary Plexus_.

_(a) The Solar Plexus_.--The veins of this plexus discharge themselves in
two directions: (1) _By a central canal_ or canals running along the bottom
of the lateral lacunæ of the plantar cushion to gain the deep layer of the
coronary plexus. (2) _By the Circumflex or Peripheral Vein of the Toe_, a
canal formed by ramifications from the solar and the podophyllous plexuses,
and following the direction of the artery of the same name. The circumflex