360 RETINA, INNER EAR, NERVES. 



p. 231 ; Zeit.f. wiss.Mik., ix, 1, 1892, p. 85) recommends that 

 eyes be put for from half an hour to three hours into 3 per 

 cent, nitric acid, then for ten days into solution of Miiller, 

 and lastly into alcohol. 



683. Staining. Dr. LINDSAY JOHNSON, writing to me, recom- 

 mends, above all things, the Ehrlich-Biondi mixture, either 

 alone or with addition of nigrosin (see 259). Used in the 

 latter way, the nuclear cells are stained pale brown, and 

 nucleoli a darker brown; whilst the Muller fibre layers, 

 molecular layers, and rods are stained a beautiful green, 

 varying from yellowish to bluish green according to thickness 

 of specimen and strength and length of action. 



RAMON Y CAJAL employs the rapid chromate of silver method 

 of Golgi, as given below ( 715). 



KUHNT (see last section) employs Pal's modification of 

 Weigert's haematoxylin process. 



DOGIEL employs the methylen-blue method, as given in 

 H7, 119. 



SCHAFPER (Sitzb. k.Acad. Wiss. Wien, xcix, 1890, 3, p. 110; 

 Zeit.f. wiss. Mik., viii, 2, 1891, p. 227) recommends mordant- 

 ing sections in 1 per cent, chromic acid for some hours, 

 washing for a short time only with water, staining for twenty 

 hours in Kultschitzky's acetic acid hasmatoxylin (post, 697), 

 and differentiating for twelve hours in Weigert's ferricyanide 

 solution. 



KRAUSE (1. c., 685) obtains instructive preparations by treating fresh 

 retina with perchloride of iron or of vanadium in 1 per cent, solution, and 

 then with a 2 per cent, solution of tannic or pyrogallic acid. These reagents 

 only stain the granule layers and the nuclei of the ganglion-cells. The ele- 

 ments of the other layers may then be stained with Sauref uchsin, or some 

 other anilin. 



LENNOX (Arch.f. Ophthalm., xxxii, 1 ; Zeit. f. wiss. Mik., iii, 3, 1886, 

 p. 408 ; and Journ. Roy. Mic. Soc., 1887, p. 339) has been applying 

 Weigert's hrematoxylin method to the retina, with some remarkable results. 



CUCCATI (1. c., last section) stained with concentrated aqueous solution of 

 Sauref uchsin, and mounted in balsam. 



See also BERNHEIMER, Sb. k., Akad. Wiss. Wien, 1884; or Journ. Roy. 

 Mic. Soc., 1886, p. 167 ; and KAMON Y CAJAL, Rev. trim, de Hist. Norm, y 

 Path., i, 1888, p. 1 ; Anat. Anz., 1889, p. Ill ; Zeit.f. wiss. Mik., v, 3, 1888, 

 p. 373, and vi, 2, 1889, p. 204. 



684. Sections. Some workers recommend celloidin ; but 

 I see no reason whatever for not employing paraffin. Sections 



