NBOEOGLIA, AND SENSE ORGANS. 445 



GoLGi's sublimate impregnation (Cox's form) has also been 

 successfully employed by Krause and Eamon. 



The bichromate-and-silvev method serves for the study of 

 the fibres of Miiller and neuroglia cells, as well as neurones. 

 Weigert's neuroglia stain does not give good results. 



Lennox (Avch.f. Opthalm., xxxii, 1 ; Zelt. iviss. Mile, iii, 1886, p. 408) 

 has used Weigert's hajmatoxylin method. 



KuHNT (Jen. Zeit. Naturw., Bd. xxiv, H. 1, 1889, p. 177) employs 

 Pal's modification. Similarly Schaffbe [Sitzb. Akad. wiss. Wieu., xcix, 

 1890), 3, p. 110 ; Zeit. loiss. Mile, viii, 1891, p. 227). These methods give 

 a differential stain of rods and cones. 



For the zonula and ciliary body see Maw as, Arch. d'Anat. micr., xii, 

 1910, p. 103. 



847. Dissociation. — For maceration preparations you may 

 use weak solutions (0-2 to O'S per cent.) of osmic acid for 

 fixation, and then macerate in 002 per cent, chromic acid 

 (M. Schultze), or in iodised serum (M. Schultze), or in 

 dilute alcohol (Landolt), or in Miiller's solution, or (Eanviee, 

 Traits, p. 967) in pure water, for two or three days. Thin 

 {Journ. of Anat., 1879, p. 139) obtained veiy good results 

 by fixing for thirty-six to forty-eight hours in one-third 

 alcohol, or in 25 per cent, alcohol, and then staining and 

 teasing. 



ScHiEPFEEDECKEE macerates fresh retina for several days in 

 the methyl mixture, § 543. 



Keause {Intern. Monatsschr. Anat., 1884, p. 225) recom- 

 mends treatment for several days with 10 per cent, chloral 

 hydrate solution ; the rods and cones are well preserved. 



Inner Ear. 



848. Inner Ear, Dissection. — For the dissection of the human ear 

 see PoLiTZEE, " Die anatomische u. histologische Zergliederuug d. men- 

 schliohen Gehoroganes,'' Stuttgart (Enke), 1S89 {Zeit. wiss. Mile, vii, 

 1890, p. 364). Amongst the lower mammalia, the guinea-piij is a 

 favourable subject, as here (as with souie other rodents) the cochlea 

 projects freely into the cavity of the bulla, and may be easily removed 

 with a scalpel and brought into a fixing liquid, and opened therein. 

 With fishes and amphibia also the meml_)ranous labyrinth may easily 

 be got away. 



849. Preparation. — Schwalbe [Beitr. z. Fhys., 1887; Zeit. 

 wiss. Mik., iv, 1887, p. 90). — Fix (cochlea of guinea-pig) for 



