472 APPENDIX. 



down it as soon as evaporation has produced a very slight 

 solidification, and the evaporation must not be artificially 

 hastened.) 



869. The Water and Albumen Section-fixing Method. A careful 

 and detailed description of the method shortly described after HENNEGUY 

 ( 328) is given by OHLMACHEE (Journ. Amer. Med. Ass., April, 1893), who 

 has independently worked out the same process. 



870. Monobromated Camphor for Narcotisation. Since 

 writing the note calling attention to this new method in 

 811 I have learnt that the method is not applicable to 

 marine organisms, as the camphor is not sufficiently soluble 

 in salt water. But for the most diverse fresh-water forms 

 it has proved highly convenient. 



871. Gilson's Mercuro-nitric Fixing Mixture. I regret to 

 find that by an unaccountable oversight I have omitted to 

 mention this liquid, the formula of which has been several 

 times published. I am indebted to Prof. GILSON for kindly 

 sending me the latest formula, which is as follows : 



Nitric acid of 46 strength (this 

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



cent., nearly) . . . . 78 c.c. 



Glacial acetic acid . . . .- 22 



Corrosive sublimate .- . . 95 grms. 



60 per cent, alcohol . . . 500 c.c. 



Distilled water .... 4400 



When required for 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 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 (not iodide of 

 potassium, which would precipitate the sublimate). 



This mixture affords in general a faithful and delicate fixa- 

 tion, 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 favorable for staining. The 

 liquid has a high degree of penetration. A treatment fora 

 few days with it will serve to remove the albumen from the 

 ova of Batrachians. 



