58 CHAPTER V. 



Nitric acid of 46 strength (this 

 would be sp. gr. 1'456, or 80 per 

 cent., nearly) . . . .15 c.c. 



Glacial acetic acid . . 4 ,, 



Corrosive sublimate . . .20 grins. 



60 per cent, alcohol . . . 100 c.c. 



JDistilled water . . . . 880 



When required fur marine animals add a few crystals of 

 iodine,, which will prevent the formation of precipitates of 

 sea salts. If in any case the preparations should 1 show a 

 granular precipitate,, due probably to an abundance of 

 phosphates in the tissues, the precipitate may be removed 

 by washing with water containing a little tincture of iodine. 

 I have tried this mixture and find that it affords in 

 general a faithful and delicate fixation,, and gives to tissues 

 an excellent consistency. Objects may remain in it for a 

 considerable time without hurt. Tissues are left in a state 

 very favourable for staining. The liquid has a high degree 

 of penetration. A treatment for a few days with it will 

 serve to remove the albumen from the ova of Batrachians. 

 This liquid may be recommended to beginners, as it is 

 very easy to work with. For some objects, as I found, 

 the proportion of sublimate may be increased with ad- 

 vantage. 



CARAZZI (MittJi. Zool. Stnt. Neapel, xii, 1896, p. 381) 

 takes one litre of 1 per cent, sodium chloride solution and 

 adds to it 20 grammes of sublimate, dissolved in 100 c.c. of 

 70 per cent, alcohol, 15 c.c. of concentrated nitric acid, and 

 5 c.c. of glacial acetic acid. Very small objects to be fixed 

 for one to two hours, larger ones four to six. Wash out in 

 iodine-alcohol for two to twenty-four hours. 



KOSTANKOKI and SIKDLKOKC (Arch. f. inlk. Anaf., xlviii, 

 1896, p. 181) take a mixture of saturated sublimate solution 

 and 3 per cent, nitric acid in equal parts, or a mixture of 

 equal p;irts of sublimate solution, 3 per cent, nitric acid, and 

 absolute alcohol, fix for twenty-four hours, and wash out in 

 iodine-alcohol. 



71. Picro-sublimate Mixtures. R-ABL'S (Zeit f. W!*H. Mik., 

 xi, '2, 1SD4, p. 1C).")). Sublimate, saturated solution in water, 

 1 vol.; ;i similar solution of picric acid, 1 vol.; distilled 



