On the development of the retina and optic nerve, and of the membranous labyrinth and auditory nerve / by Henry Gray.

  • Gray, Henry, 1827-1861.
Date:
1850
Catalogue details

Licence: Public Domain Mark

Credit: On the development of the retina and optic nerve, and of the membranous labyrinth and auditory nerve / by Henry Gray. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Explanation of the Plates. PLATE VIII. Fig-. 1. An embryo chick at the thirty-first hour of incubation. Fig. 2. An embryo chick at the thirty-third hour. Fig. 3. An embryo chick at the thirty-sixth hour. The first rudiment of the eye is here seen to be visible in the form of a protrusion from the anterior cere- bral cell. Fig. 4. An embryo chick at the forty-sixth hour. The optic vesicle is seen now very distinct, presenting a slight contraction at its connection with the cerebral cell from which it arises. Fig. 5. The cephalic extremity of a chick at the same period more highly magnified. This Plate is intended to represent the cavity which exists both in the cere- bral cell and optic vesicle, and the communication between them. Fig. 6. The cephalic extremity of an embryo at the fifty-fifth hour viewed from the dorsal aspect, principally intended to represent the mode of formation of the crystalline lens. Fig. 7- The under surface of the eye of a chick at the seventieth hour. This figure shows the spherical form of the eyeball, its contracted tubular end, the optic nerve, the mode of formation of the lens, and the fissure which exists on the under surface of the eye. PLATE IX. Fig. 8. The cephalic extremity of an embryo chick at the sixty-second hour (lateral view). Fig. 9. In this Plate the retina is seen overlapping the margin of the lens at the latter half of the third day. Figs. 10 and 11. The eye of an embryo chick on the fourth day. Fig. 12. The eye of an embryo chick on the fifth day. Fig. 13. In this Plate the first rudiment of the ear is visible in the form of a small vesicular protrusion from the central part of the medulla oblongata (from an embryo chick at the fiftieth hour of incubation). Fig. 14. An embryo chick at the fifty-sixth hour. The ear-bulb is now seen to be of a pyriform shape, and communicating with the cavity from which it arises. Fig. 15. The cephalic extremity of an embryo chick at the sixty-fifth hour of incuba- tion. The rudimentary vestibule and auditory nerve are now seen fully formed. Fig. 16. The ear of an embryo chick at the seventy-second hour of incubation. The