MACERATION CORROSION 247 



573. Hydrochloric Acid. Konigstein {Sitzh. Akad. Wicn, Ixxi, 1875) 

 takes (for gold-impregnated corneae) equal parts of the concentrated 

 acid glycerin, and water ; Freud (ibid., Ixxviii, 1879, p. 102, for nerve- 

 impregnations), 10 parts of acid, 7 of water, 'S of glycerin ; and 

 ScHUBERG and Schroder (Zeit. iviss. ZooL, Ixxvi, 1904, p. 516) take 

 (for fresh muscles of Hirudinea) hydrochloric acid of 5 per cent. 



574. Bela Haller's Mixture (Morphol. Jahrb., xi, p. 321). 

 One part glacial acetic acid, 1 part glycerin, 2 parts water. For 

 the central nervous system of Mollusca a maceration of thirty 

 to forty minutes may be sufficient. 



575. Sulphuric Acid (Ranvier, Traite, p. 76). Macerate for 

 twenty-four hours in 30 grm. of water, to which are added 4 to 5 

 drops of concentrated sulphuric acid. Agitate. For nasal mucosa, 

 crystalline, retina, etc. 



Odenius found very dilute sulphuric acid to be the best reagent 

 for the study of nerve endings in tactile hairs. He macerated 

 hair-follicles for from eight to fourteen days in a solution of from 

 3 to 4 grm. of " English sulphuric acid " to the ounce of water. 



Hot concentrated sulphuric acid serves to dissociate horny 

 epidermal structures (horn, hair, nails). 



576. Oxalic Acid. Maceration for many days in concentrated 

 solution of oxalic acid has been found useful in the study of nerve- 

 endings. 



577. Schiefferdecker's Methyl Mixture (for the retina) 

 [Arch. mik. Anat., xxviii, 1886, p. 305). Ten parts of glycerin, 

 1 part of methyl alcohol, and 20 parts of distilled water. Macerate 

 for several days (perfectly fresh tissue). 



578. Gage's Picric Alcohol {Proc. Anier. Soc. of Microscopists, 

 1890, p. 120). Ninety-five per cent, alcohol, 250 parts ; water, 

 750 ; picric acid, 1. Recommended especially for epithelia and 

 muscle. A few hours suffice. 



579. Chloral Hydrate. In not too strong solution, from 2 to 5 

 per cent, for instance, chloral hydrate is a mild macerating agent 

 that admirably preserves delicate elements. Lavdowsky (Arch, 

 rnik. Anat., 1876, p. 359) recommends it greatly for salivary 

 glands, HiCKSON {Quart. Journ. Mic. Sci., 1885, p. 244) for the 

 retina of Arthropods. 



580. Lysol (Reinke, Anat. Anz., viii, 1892. p. 582). Ten per 

 cent, solution in distilled water or in water with alcohol and 

 glycerin. Spermatozoa of the rat or cortical cells of hairs arc 

 said to be resolved into fibrils in a few minutes, epithelial cells 

 of salamandra to be dissociated instantaneously. 



DIGESTION 



581. Digestion is maceration in organic juices, which by dis- 

 solving out some of the constituents of tissues earlier than others 

 serves to isolate those which resist. The chief liquids emi^loyed 



