splenial

File:Image from page 37 of "Water reptiles of the past and present" (1914) (14586264740).jpg; the splenial (labeled "sp") is visible on the interior surface]]

File:Dimetrodon_skull_lateral.svg Dimetrodon, showing location of the splenial]]

The splenial is a small bone in the lower jaw of reptiles, amphibians and birds, usually located on the lingual side (closest to the tongue) between the angular and surangular.Romer, A. S. (1956). Osteology of the Reptiles. 772 pp. Chicago & London.Watson, D. M. S. (1912). LXVII.—On some reptilian lower jaws. Journal of Natural History, 10(60), 573-587.