Journal of morphology . A? A? atria; P. air-sac passages; S. air-sac (the same as in Fig, 21); Ay, artery ; V. vein. /oiinuil 0/ ? Morpliokn/i/ I ol. VIII. PI. THE DEVELOPMENT OF THE OPTIC VESICLES IN AMPHIBIA. ALBERT C. EYCLESHYMER. Notwithstanding the searching observations made duringthe past score of years, but little has been found which wouldessentially modify the statements of the pioneer embryologists:that the eyes first appear as a pair of diverticula budding outfrom the sides of the anterior cerebral vesicle. It should not be said, however, that we are wholly withoutobservations
Journal of morphology . A? A? atria; P. air-sac passages; S. air-sac (the same as in Fig, 21); Ay, artery ; V. vein. /oiinuil 0/ ? Morpliokn/i/ I ol. VIII. PI. THE DEVELOPMENT OF THE OPTIC VESICLES IN AMPHIBIA. ALBERT C. EYCLESHYMER. Notwithstanding the searching observations made duringthe past score of years, but little has been found which wouldessentially modify the statements of the pioneer embryologists:that the eyes first appear as a pair of diverticula budding outfrom the sides of the anterior cerebral vesicle. It should not be said, however, that we are wholly withoutobservations pointing toward an earlier differentiation. Bis-choff, Kolliker, His, Van Beneden and others have noted thatin mammals the optic vesicles appear extremely early. Heape^finds in an early stage of the Mole, where the neural folds areclosed along the center of the embryo, that at the anteriorend the floor of the neural groove, on either side, is swollen,and on the outer and anterior edge of the two masses a deepnarrow groove indicates the commencement of the formationof the optic organs. Keibel ^ describes a like condition inthe embryo of the guinea-pig. This
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Keywords: ., bookautho, bookcentury1800, bookdecade1890, booksubjectphysiology
