. The development of the chick : an introduction to embryology. Embryology; Chickens -- Embryos. 294 THE DEVELOPMENT OF THE CHICK cochlearis; the tip of the lagena in its growth ventralward has reached the horizontal level of the notochord. The sacculus is barely indicated yet, but is clearly seen on the seventh day as a slight protuberance on the median surface of the uppermost part of the pars inferior; it lies in front of the lower end of the endolymphatic duct at a slightly lower level and is separated by two depressions above and below, from the anterior ampulla and the ductus cochlearis
. The development of the chick : an introduction to embryology. Embryology; Chickens -- Embryos. 294 THE DEVELOPMENT OF THE CHICK cochlearis; the tip of the lagena in its growth ventralward has reached the horizontal level of the notochord. The sacculus is barely indicated yet, but is clearly seen on the seventh day as a slight protuberance on the median surface of the uppermost part of the pars inferior; it lies in front of the lower end of the endolymphatic duct at a slightly lower level and is separated by two depressions above and below, from the anterior ampulla and the ductus cochlearis respectively. The furrows above the sacculus and below the ampulla of the frontal semicircular canal mark the boundary between the pars superior and Fig. 172. — Model of the auditory lal)yrinth of the right side of a chick embryo of 8 days and 17 hours; external view. (After Rothig and Brugsch.) A. a., Ampulla of the anterior semicircular canal. A. 1., Ampulla of the lateral semicircular canal. A. p., Ampulla of the posterior semicircular canal. C. a., Anterior semicircular canal. C. 1., Lateral semi- circular canal. C. p., Posterior semicircular canal. Sa. e., Endolymphatic sac. U., Utriculus. Other abbreviations as before. A day later (Fig. 172), these furrows have cut in deeper and have become continuous on the median surface; the lagena has enlarged distally, and the sacculus is a hemispherical protuber- ance. The tip of the lagena lies beneath the hind-brain ( Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Lillie, Frank Rattray, 1870-1947. New York : Henry Holt
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Keywords: ., bookauthorlilliefrankrat, bookcentury1900, booksubjectembryology
