Internal Ear Angioarchitectonic of Serpents

ISBN-13: 9783540088363 / Angielski / Miękka / 1978 / 44 str.

M. La1/4dicke

Opis

Serpents lack an external ear, a tympanic membrane, a tympanic cavity, and a Eusta- chain tube. These negative but very significant characteristics are seen phylogenetically, especially in connection with the reduction of the eye (Le., Nopsca, 1923; N.B., today Pachyophis is grouped together with the Simoliophidae, furthermore Mahendra, 1938; Walls, 1940, 1942; Bellairs and Underwood, 1951). Other authors mention these cha- racteristics in connection with characteristics of ingestion (Berman and Regal, 1967). They claim that the formation of a tender tympanic membrane and a tympanic cavity is incompatible with the mobility of the quadratum and its adjacent musculature. The energy of sound can be transmitted either by the bones of the skull or the otic capsule or by the intercalare (medially adjacent to the quadratum) with the stapes and the. base of the columella (for the intercalare or rather the extracolumella see De Beer, 1926 and 1937; McDowell, 1967). The vibrations of the apparatus added to the vesti- buloquadratum type (Sertakowa, 1950) initiate a movement of the perilymph in the sinus pericapsularis (sinus juxtastapedialis), in the cisterna perilymphatica and in the scala tympani with the helicotrema. This stimulates the sense organs of the papilla basilaris located on the membrana basilaris in the pars limbi of the ductus cochlearis filled with endolymph.

Spis treści

1. Introduction.- 2. Materials and Methods.- 3. Results.- 3.1 Arteries and Veins of the Membranous Labyrinth.- 3.2 Capillary Areas of the Sinus Utriculi Superior, the Utriculus With Recessus and Maculae, and the Sinus Utriculi Posterior.- 3.3 Capillary Areas of the Semicircular Ducts and Their Ampullae With Cristae.- 3.4 Capillary Areas of the Sacculus, the Ductus Endolymphaticus, the Saccus Endolymphaticus, and the Ductus Utriculosaccularis.- 3.5 Capillary Areas of the Ductus Cochlearis With the Pars Lagena and the Pars Limbi.- 3.6 Vessels and Capillary Regions of the Intracapsular Perilymphatic System.- 4. Discussion.- 5. Summary.- 6. References.- 7. Subject Index.