(1) The circumvallate and foliate papillae are characterized not only by their position, but also by presence of several taste buds which open through the external orifice of the gustatory canal into the cavity of the vallum, or furrow, which divides the two folds of the lingual mucosa.
(2) The main excretory duct, which opens at the bottom of the vallum, shows a stratified epithelium.
(3) In two species of the Sorex a papilla in the vallate papilla was surrounded by two separated trenches, but in the other species it was surrounded by only a continuous trench and a clear vallum.
(4) The latter opens in the vallum which surrounds the circumvallate papillae and in the groove of the foliate papillae.
(5) The perioplic segment extends along the internal surface of the claw fold (vallum).
(6) Some of them are located at the limit between glottis and supraglottis; therefore one may argue that the so-called "biological vallum", which hinders the downward propagation of supraglottic cancers is not only due to the interruption of lymph ways between vestibulum and vocal chords but also to the presence of this thick connective barrier.
(7) A group of diabetic patients was submitted to a capillaroscopic examination at the level of the peri-ungual vallum and to a fluoroangiographic examination of the retina, for the evaluation of possible correlations between vessel conditions in to various districts.