ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 785 



Lugol's solution 3 c.cm.). The film is then washed with water and 

 then immersed for 10 minutes in a 0*5 p.c. aqueous solution of sodium 

 thiosulphate. After removal it is again washed with water and then 

 stained with fresh Giemsa solution (1 drop to 1 c.cm. of water, or 2 c.cm. 

 for longer staining) for 1 to 12 hours or longer; after the first half - 

 hour it is necessary to pour off the stain and replace with a fresh lot. 

 After staining, the preparation is treated to the following series : (a) 

 aceton 95, xylol 5 ; (b) aceton 70, xylol 30 ; (c) aceton 70, xylol :;<• ; 

 (d) pure xylol. Mount in cedar- wood oil. 



Staining Blood Smears.* — Hayhurst stains films of blood with the 

 following solutions, {a) Water soluble eosin 1, methyl-alcohol abs. 100. 

 (l>) Medicinal methylen-blue 1, methyl-alcohol abs. 100. Solution a is 

 allowed to act for J to 1 minute, and then the preparation is at once and 

 without further treatment immersed in solution b for ^ to 1 minute. 

 After washing in water for \ to 1 minute the preparation is dried with 

 blotting-paper and mounted in cedar-wood oil. During manipulation 

 the film should be covered in order to prevent evaporation. 



Detection of Tubercle Bacilli in the Placenta.f — J. Novak and 

 F. Ranzel, by means of the antiformin method, have demonstrated in 

 four cases out of six the presence of tubercle bacilli in the placenta of 

 tuberculous women. Pieces of placenta were finely divided and washed 

 until free from blood. Part was then treated with 20 p.c. antiformin, 

 while another portion was fixed in alcohol for 24 hours, dried and ground 

 in a mortar to a fine powder, and then treated with antiformin. By 

 this means the tissue and non-acid-fast bacteria are dissolved. The 

 second method gave the better results, solution being effected in 4 to 5 

 hours. Alcohol in the proportion of 3 to 2 was added in order to reduce 

 the specific gravity and facilitate sedimentation. The sediment was 

 washed and stained for tubercle bacilli. 



Indian-ink Method in Parasitology.}— B. G-alli-Valerio has used 

 the Chinese ink method of Burri in studying spirochetes, sarcinas and 

 bacteria. This ink he uses in dilutions of 1 in 9, or 1 in 3, in distilled 

 water. The solutions are sterilized, and keep well. A few drops of 

 formalin are added. Excellent preparations of these parasites, white 

 upon a dark ground, are thus obtained, and continued investigations 

 are not accompanied with fatigue. 



Staining Nervous Tissues with Methylen-blue. §— After giving 

 an account of the methods employed by Ehrlich and others for the 

 demonstration of nerve-cells and nerve-fibres by means of this stain, 

 S. Michailow describes his own technique as applied to the study of 

 these structures in the mammalian heart. After the animal has been 

 killed, the heart is removed and then left untouched for two hours. 

 After this interval, it is washed in Ringer-Locke's saline solution at 

 body temperature until the washings are no longer discoloured. The 



* Journ. American Med. Assoc, Hi. (1909) No. 14. 

 t British Med. Journ. (1910) ii. epit. 125. 

 j Centralbl. Bakt., lte Abt. Orig., lvi. (1910) pp. 46-7. 

 § Zeitschr. wiss. Mikrosk., xxvii. (1910) pp. 1-21. 



