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 vein terminates by forwarding branches to concur in the formation of the superficial coronary plexus. _(b) The Podophyllous or Laminal Plexus_.--The podophyllous veins anastomose below with the circumflex vein of the solar plexus, and above with the veins of the coronary plexus. _(c) The Coronary Plexus_.--This proceeds from the podophyllous, the intra-osseous, and the solar networks, and consists of a _central_ and _two lateral parts_. The _central_ portion lies between the lateral cartilages and immediately under the coronary cushion. The _lateral portions_ are ramifications on both surfaces of the lateral cartilages. The ramifications on the lateral cartilages may be again distinguished as _superficial_ and _deep_. The superficial layer is distributed over the external face of the cartilage, forming thereon a dense network, and finally converges towards the superior limit of the plexus to form ten or twelve principal branches, which again unite to form two large vessels. These vessels, by their final fusion at the lower end of the first phalanx, constitute the digital vein. The deep layer is formed, as before described, by ascending branches from the posterior parts of the podophyllous and solar plexuses, and by branches from the intra-osseous system of the pedal bone. The veins of this deep layer finally drain into the two vessels proceeding from the superficial layer, which go to the formation of the digital vein.