238 CHAPTER xrx. 



Another method is as follows : Serum is mixed with a 

 large proportion of tincture of iodine ; the precipitate that 

 forms is removed by filtration^ and there remains a strong 

 solution of iodine in serum. This should be kept in stock, 

 and a little of it added every two or three days to the 

 serum that is intended for use. In general for maceration 

 purposes a serum of a pale brown colour should be em- 

 ployed. 



406. Artificial Iodised Serum [Fuey, Das Mikroscop, 6 Aufl.,- 

 1877, p. 75). — Distilled water 270 grms., white of egg 30, 

 sodium chloride 2'5. Mix, filter, and add tincture of iodine. 



407. Migitla's Grlyoerized Blood-serum (see the paper in Zeit. f. 

 wiss. Mill.., vii, 2, 1890, p. 172). 



408. Chloride of Calcium (Haeting, Das Mihro.<lwp, 2 Anfl,, p. 297). 

 — The acpieous solution, either saturated or diluted with 4 to 8 parts of 

 water, lias a low refractive index and does not dry up. 



409. Acetate of Potash (Max Schultze, Arch. mik. Anat., vii, 1872, 

 p. 180), — A nearly saturated solution in water, The index of refraction 

 is lower than that of glycerin. 



410. Syrup. — A good strength is equal parts of loaf sugar 

 and water. Dissolve by boiling. To preserve it from 

 mould, chloral hydrate may be dissolved in it (1 to 5 per 

 cent.) — I have used as much as 7 per cent., and found no 

 disadvantage — or carbolic acid (1 per cent.). 



It may be used as a mounting medium, but there is always 

 risk of the sugar crystallising out. 



Fabre-Domeegub (Bull. Soc, Philomath, ix, 1899, p. 115) 

 dissolves 200 parts of suger in 400 of water, and adds 1 

 part of formaldehyde, and camphor to saturation. 



411. Chloral Hydrate. — 5 per cent, in water (Ladowsky, 

 Arch. f. mih. Anat., 1876, p. 359). 



Or, 2-5 per cent, in water (Beady, British. Gopepods). 

 Or, 1 per cent, in water (Mqnson, Journ. Roy. Mic. Soc, 

 188], p. 81.7). 



