274 CHAPTER XXIII. 



osmic acid are removed ; they then remain fof a day in O'l 

 per cent, acetic acid, are washed in water, stained in Beale's 

 carmine, and preserved in glycerin. 



For Actinise the osmic acid is taken weaker, 0'04 per cent. ; 

 both the solutions are made with sea water ; and the washing 

 out is done with 0"2 per cent, acetic acid. If the maceration 

 is complete, stain with picro-carmine ; if not, with Bealk's 

 carmine. 



535. MoBiKS's Media (Morpli. Jahrh., xii, 1887, p. 174). 



1. One part of sea water with 4 to 6 parts of 0'4 per cent, solution of 

 bichromate of potash. 



2. 025 per cent, chromic acid, 01 per cent, osmic acid, O'l per cent, 

 acetic acid, dissolved in sea water. For Lamellibranchiata. Macerate 

 for several days. 



536. Nitric Acid. — Most useful for the maceration of muscle. 

 The strength used is 20 per cent. After twenty-four hours' 

 maceration in this, isolated muscle-fibres may generally be 

 obtained by shaking the tissue with water in a test-tube. 

 Preparations may afterwards be washed with water and put 

 up in strong solution of alum, in which they may be pre- 

 served for a long time (Hopkins, Proc. Amer. Soc. of Micro- 

 scopids, 1890, p. 165). 



Maceration is greatly aided by heat, and at a temperature 

 of 40° to 50° C. may be sufficiently complete in an hour 

 (G-age). 



A mixture of equal parts of nitric acid, glycerin, and water 

 is recommended by Maucacci {Arcli. Ital. Biol., iv, 1883, 

 p. 293) for smooth muscle. 



537. Nitric Acid and Chlorate of Potash (Kijhne, Veber die 

 jierliiherischen Endorgane, etc., 1862; Ranviee, Traite, p. 79). 

 — Chlorate of potash is mixed, in a watch-glass, with four 

 times its volume of nitric acid. A piece of muscle is buried 

 in the mixture for half an hour, and then agitated with water 

 in a test-tube, by which means it entirely breaks up into 

 isolated fibres. 



538. Nitric and Acetic Acid (Apathy, Zeit. iciss. Mile., x, 1898, 

 p. 49). — 3 vols, glacial acetic acid, 3 of nitric acid, and 20 each of water, 

 glycerin, and absolute alcohol. Macerate leeches for twenty-four hours, 

 and bring them into 70 per cent, alcohol, in which they swell; then 



