from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The fluid in the space between the membranous and bony labyrinths of the inner ear.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An extracellular fluid found in the scala tympani and scala vestibuli of the cochlea.
from the GNU version of the Collaborative International Dictionary of English
- n. The fluid which surrounds the membranous labyrinth of the internal ear, and separates it from the walls of the chambers in which the labyrinth lies.
from The Century Dictionary and Cyclopedia
- n. The clear fluid contained within the osseous labyrinth of the ear, surrounding the membranous labyrinth: distinguished from endolymph. Also called liquor Cotunnii.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the bodily fluid that fills the space between the bony labyrinth and the membranous labyrinth of the inner ear
Between the bony walls of the passages and the membranous bag inside is a thin, clear fluid, the _perilymph_.
When, therefore, the perilymph is shaken it communicates the impulse to the fluid (endolymph) contained in the inner membranous bag.
Every time the stirrup bone is pushed in and drawn out of the oval window, the watery fluid (the perilymph) in the vestibule and inner ear is set in motion more or less violently, according to the intensity of the sound.
The outer portion is surrounded by a membrane which serves as periosteum to the bone and, at the same time, holds the liquid belonging to this part, called the perilymph.
These are cavities hollowed out of the substance of the bone, and lined by periosteum; they contain a clear fluid, the perilymph, in which the membranous labyrinth is situated.
The osseous labyrinth is lined by an exceedingly thin fibro-serous membrane; its attached surface is rough and fibrous, and closely adherent to the bone; its free surface is smooth and pale, covered with a layer of epithelium, and secretes a thin, limpid fluid, the perilymph.
The membranous labyrinth is lodged within the bony cavities just described, and has the same general form as these; it is, however, considerably smaller, and is partly separated from the bony walls by a quantity of fluid, the perilymph.
If, as has been supposed by some physiologists, the stria vasculosa is really the source of the endolymph, this state of affairs must have a marked influence on the functions of the auditory apparatus and the static apparatus, for pressure differences between the endolymph and the perilymph spaces must be present.
The whole of the labyrinth is membranous, and contains a fluid, the endolymph; between the membranous wall of the labyrinth and the enclosing bone is a space containing the perilymph.
If the vibrations of the perilymph have originated from a sound with a high enough pitch, it will cause a vibration in the basilar and vestibular membrane in the scala vestibuli.