Slightly posterior to the anterior end of the cavum medium the foramen for the ramus externus narium (_r. ext. n. f._) and ramus medialis narium (_r. med. n. f._) opens ventromedially into the floor of the septum nasi (Fig. 4). The ventral closure of the floor of the foramen completes the solum nasi, marks the anterior end of the recessus medialis of the cavum inferior, and differentiates the roof of the recess, the crista intermedia (_cr. int._), from the solum (Fig. 5). The crista intermedia joins the laminae superior and inferior and joins them for a short distance to the septum nasi medially. The anterolateral part of the cavum inferior (_cav. inf._) lies ventrolateral to the cavum medium, and extends medially to join the medial recess. The fusion of the two recesses of the cavum inferior completely separates the lamina inferior from the solum nasi (Fig. 6). Near the level of the union of the recessus lateralis and recessus medialis of the cavum inferior, the crista intermedia separates from the septum nasi, and the lamina superior diverges at its mid-width to accommodate the septomaxillary (_spmax._) (Figs. 5 and 6). The lateral remnant of the lamina superior and transition zone between the lamina superior and lamina inferior is short and is quickly replaced by connective tissue. Slightly posterior, the distal edge of the lamina inferior diverges laterally as a small process, which lies dorsal to the pars facialis (_p. fac._) of the maxillary. This part of the lamina inferior terminates posteriorly at the level of confluence between the cavum principale and lateral recess of the cavum inferior. Slightly posterior to the divergence of the crista intermedia from the septum nasi, the crista terminates, thereby separating the lamina superior and the lamina inferior from one another (Figs. 6 and 8). The lamina superior terminates at the level of the infundibulum (_inf._, Fig. 7), whereas the lamina inferior extends posterolaterally, increases greatly in depth and joins the laterally ascending oblique cartilage (_obl. c._) to form the planum terminale (_pla. ter._, Fig. 10). The crista subnasalis (_cr. sub._, Fig. 6) differentiates from the lateral edge of solum nasi adjacent to the maxillary in sections just posterior to the confluence of the recessus medialis and the recessus lateralis. The crista persists as a rod of cartilage which gradually diminishes in size and terminates at the posterior level of the septomaxillary.