216 SUMMARY OF CUKRENT RESEARCHES RELATING TO 



when treated with certain lixatives. They find that A"an Gehuchten's 

 fluid (alcohol 60, chloroform 30, acetic acid 10) fixes less than a tenth 

 of the compounds of fatty acids ; Lindsay's fluid (bichromate of potas- 

 sium 2*5 p.c. 70, osmic acid 1 p.c. 10-, bichloride of platinum 1 p.c. 15, 

 acetic acid 5) fixes a fifth ; the fluids of Laguesse (osmic acid 2 p.c. 

 4 parts chromic, acid 1 p.c. 8 parts, acetic acid 1 drop) and Regaud 

 (bichromate of potassium 3 p.c, 24 formahn 40 p.c, (> parts) fix about 

 third, and Miiller's fluid a half. The authors infer that the ordinary 

 methods of fixing compounds of fatty acid are inadequate when tissues 

 are treated with alcohol and xylol. 



Preparation of Ascaris Ova.* — P. Cerfontaine gives an account of 

 his methods of dealing with the eggs of Ascaris, in the preparation of 

 the material for section. After preliminary remarks upon the collection 

 of the material and artificial incubation, by means of which eggs may 

 be obtained at any desired stage of development, he describes the fixing 

 and clearing processes. The eggs are killed by immersion for several 

 hours in a liquid composed of absolute alcohol and glacial acetic acid in 

 equal proportions, to which is added a small quantity of picric acid. 

 They are then transferred to 94 p.c. alcohol. This is changed 

 several times until the yellow colour is lost. Then, after treatment with 

 absolute alcohol, the material is placed in a bath containing 5 ccm. of 

 essence of cloves and 500 ccm. of absolute alcohol. This is loosely 

 covered so that the alcohol evaporates slowly. When the fluid reaches 

 a bulk of one-tenth of the original volume, a mixture of 10 ccm. essence 

 of cloves and 200 ccm. of absolute alcohol is added, and the same slow 

 concentration is allowed to proceed until one-tenth of the original bulk 

 of fluid is reacted. Then a third mixture (essence of cloves 20 ccm., 

 collodion 20 ccm., absolute alcohol 200 ccm.) is added, and the con- 

 centration process repeated. Then the eggs are transferred to cedar 

 wood oil and then embedded in paraffin. 



(4) staining- and Injecting-. 



New Fixing and Staining Methods.f — A. v. Sziits describes 

 improved methods for dealing with certain classes of tissue. For plasma 

 staining he recommends a fixing fluid containing 1 p.c platinum 

 chloride solution 15 ccm., formalin 15 ccm., concentrated sublimate 

 solution 30 ccm. After 16 to 24 hours fixation, the tissue is well 

 washed in running water and then passed through mounting alcohols. 

 The sublimate is removed by iodine alcohol. The paraffin sections, 

 mounted on albumenized slides, are treated with chloroform and 

 chloroform-alcohol, passed down through alcohols to distilled water 

 and stained with Heidenhain's iron-hsematoxylin. Then, after washing 

 with distilled water, they are treated with 5 p.c. aluminium acetate for 



* Zeitschr. wiss. Mikrosk., xxix. (1912) pp. 305-9. 

 ; t Zeitschr. wiss. Mikrosk., xxix. (1912) pp. 289-301. 



