Quain's elements of anatomy . r substance of the membrane,composed of fibrous tissue. The greater number of the fil^res radiate fromthe attachment of the handle of the malleus (fig. 373), but there are alsocircular fibres which are situated within or mesially to the radial, andcloser to the circumference, form a dense, almost ligamentous ring. Theradial fibres are not straight, but are slightly bowed outwards, so thatbetween the most depressed point or umbo, and the attached border, themembrane is slightly convex outwardly. This shape is maintained bythe annular fibres. At the upper and anteri
Quain's elements of anatomy . r substance of the membrane,composed of fibrous tissue. The greater number of the fil^res radiate fromthe attachment of the handle of the malleus (fig. 373), but there are alsocircular fibres which are situated within or mesially to the radial, andcloser to the circumference, form a dense, almost ligamentous ring. Theradial fibres are not straight, but are slightly bowed outwards, so thatbetween the most depressed point or umbo, and the attached border, themembrane is slightly convex outwardly. This shape is maintained bythe annular fibres. At the upper and anterior part, the annular fibres stretch across themouth of a small notch in the bony ring to which the membrane is attached(notch of Eivini). The notch is occupied by a lax part of the membrane{memirana Jfaccida, Shrapnell), consisting of loose connective tissue, withvessels and nerves, and covered by skin and mucous membrane. It occa-sionally happens that a fissure or perforation is to be detected at this place. Fig. 374. l-tts^. Fig. 374.—View of the left mem- BRANA TYMPAMI AND AUDITORY OS-SICLES FROM THE INNER SIDE, ANDSOMEWHAT FROM ABOVE (). | m, malleus; i, incus ; st, stapes ;py, pyramid from which the tendonof the stapedius muscle is seenemerging ; t t, tendon of the tensortympani cut short near its insertion ;I a, anterior ligament of the malleus:the processus gracilis is concealed bythe lower fibres of this ligament; I s,superior ligament of the malleus ; I. i,ligament of the incus ; cJi, chordatympani nerve passing across the outerwall of the tympanum. The membrane is supplied with blood-vessels, but tliey are chiefly confined to the skin and mucous 5>&^^^ „fe Jt i^ proper fibrous membrane, and form a communication between the two systems on the surfaces. Those of the skin are mostly supplied by a small artery, derived from the deep auricular branch of the internal maxillary, which passes from ab
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