THE EYE. 401 



difficulties. The tubes of the lens, when fresh, are very trans- 

 parent, but in dilute chromic acid they are rendered quite dis- 

 tinct. Sections of the lens may be easily procured from prepara- 

 tions made in alcohol, or chromic acid, or from dried and hardened 

 preparations, which may be rendered transparent again by means 

 of acetic acid. The accessory organs of the eyes require no 

 particular remark, unless, with respect to the Meibomian 

 glands, it may be stated, that they are best seen in tarsi which 

 have been cleanly dissected and treated with acetic acid and 

 alkalies, and in longitudinal and transverse sections of similar 

 preparations, dried.] 



Literature. — The "Eye" as a whole : Valentin, in his 

 'Repert./ 1836 and 1837, and ' Handw. d. Physiol./ I, p. 748; 

 S. Pappenheim, 'Gewebelehre d. Auges/ Berlin, 1842; E. Briicke, 

 'Anat. Beschreib. d. menschlichen Augapfels/ Berlin, 1847; 

 W. Bowman, ' Lectures on the parts concerned in the opera- 

 tions on the eye and on the structure of the Retina and 

 Vitreous Humor/ London, 1849; A. Hannover, 'Bidrag til 

 Ojets Anatomie, Physiologie og Pathologie/ Copenhagen, 1850. 

 Sclerotica: M. Erdl, 'Disquisit. anat. de oculo/ I. ' De m. 

 sclerotica/ Monach., 1839; Bochdalek, 'Ueber die Nerven 

 der Sclerotica/ in ' Prag. Viertelj./ 1849, IV, 119. Cornea ! 

 Kolliker, ' Ueber die Nerven der Hornhaut/ in ' Mitth. d. 

 naturf/ Ges., in Zurich, 1848, No. 19 ; Rahn, ' Ueber die 

 Nerven der Hornhaut/ in ' Mitth. d. naturf.' Ges., in Zurich, 

 1850, No. 45; Luschka, 'Die Nerven der durchsichtigen 

 Augenhaut/ in ' Zeitsch. f. rat. Med./ X, p. 20, and 'Die 

 Structur der serosen Haute des Auges/ in ' Str. d. serosen 

 Haute/ Tubingen, 1851; Strube, 'Der normale Bau der 

 Cornea/ Diss., Wurzburg, 1851. Choroid and Iris : C. Krause, 

 'Ueber die Pigmenthaut, in Muller's 'Arch./ 1837, p. 33; 

 E. Briicke, c Ueber den Muse, cramptonianus u. d. Spann- 

 muskel der Chorioidea/ in Mull. 'Archiv/ 1846; Bochdalek, 

 'Beitrage zur Anatomie des Auges/ 'Prag. Viertelj./ 1850, I. 

 Retina : G. Treviranus, ' Ueber den Bau der Netzhaut/ in his 

 ' Beitragen/ Bremen, 1835 and 1837 ; C. M. Gottsche, ' Ueber 

 d. Nervenausbreitung d. Retina/ in PfafFs ' Mittheil. a. d. 

 Geb. d. Med./ 1846 [and 'Ueber die Retina im Auge der 

 Gratenfische/ in Mull. 'Archiv/ 1835, p. 457,] ; A. Michaelis, 

 in Muller's 'Archiv/ 1837, p. 12, and 'N. Acta/ T. XIX, 



ii. 26 



