5. The _cuneiform cartilages_ (as Wilson names them) are two long, slender cartilaginous laminæ which become somewhat broader at both ends. These cartilages, with their base, rest in the middle of the anterior surface of the _arytenoid cartilages_, and reach to the middle of the vocal chords, by which they are enveloped. The action of these cartilages renders possible the production of the head tones, but they are not found in every larynx. The fact that they are oftener found in the female larynx than in that of the male, and that the male larynx is mostly used in scientific investigations, as it is larger and more easily dissected, may be the reason why up to the present time no mention is made of them either in German or French manuals. They are sometimes referred to as cuneiform cartilages, or confounded with the cartilages of Wrisberg, probably because it seemed unaccountable that these important bodies should so long have escaped the attention of anatomists. From the anterior surface of the _arytenoid cartilages_, extending towards the centre of the inner wall of the _thyroid cartilage_, running diagonally through the cavity of the larynx, are stretched the two pairs of chords already more than once mentioned--the vocal chords, consisting of folds of the mucous membrane which envelopes the whole larynx. The two lower of these chords, the vocal chords strictly so called, into which the _cuneiform cartilages_ project and through which the interior thyro-arytenoid muscles run, have their points of attachment at the _arytenoid cartilages_, somewhat lower than the upper pair. Each of these parallel pairs of chords form between their lips a slit running antero-posteriorly. The slit of the upper pair is opened in the shape of an ellipse; that of the lower pair, the glottis, is very narrow. As the upper chords have their point of attachment posteriorly and higher, they form with the lower chords two lateral cavities, the ventricles. The two pairs of chords, therefore, are the free interior edges of the membrane, covering the whole larynx and extending into it to the right and the left. Only the lower vocal chords serve directly for the generation of tones. More or less stretched and presenting resistance to the air forcibly expired from the lungs through the trachea, they are thus made to vibrate. The upper or false vocal chords do not co-operate with them to generate tone, but like all the remaining parts of the mouth and throat belong to the resonance apparatus of the voice, to which also appertains the back part of the mouth, the _pharynx_, over the œsophagus, the throat, or gullet. This is separated from the anterior cavity of the mouth by the palate, which is a curtain formed by the mucous membranes of the cavity of the mouth, and the centre of which forms the pendent uvula.