384 SUMMARY OF CURRENT RESEARCHES RELATING TO 



reduced, and only at their periphery. The sections depicted in the 

 illustrations were stained by the iron-alum method. The author arrives 

 at the conclusion that the granules are neither fatty nor mitochondria, 

 and calls them pigmented liquid bodies. 



Vital Staining of Trypanosomes.* — A. Policard places between 

 slide and slip a drop of infected blood, and then applies to the edge a 

 drop of strong neutral red, dissolved in saline solution. By this method 

 certain granules are stained a brick red. The chemical nature of these 

 formations is doubtful, but they are not acid and are not degeneration 

 products. 



Golgi's Method for Examining the Internal Network of Spinal 

 Marrow Cells. f — R. Legendre found that Golgi's method for examining 

 the cells of the spinal cord could be advantageously modified by the 

 following technique : The material was fixed in Golgi's fluid — i.e. forrnol 

 (20 p.c.) 30, saturated solution of arsenious acid 30, alcohol (96 p.c.) 30, 

 for 6 to 24 hours. Then nitrate of silver (1 p.c.) for one to several days. 

 After a rapid wash in distilled water, the preparations were placed for 



1 hour in the reducer (hydroquinine 20, sulphite of soda 5, formalin 50, 

 distilled water 1000). This was followed by washing in distilled water, 

 alcohols, paraffin sections. In this procedure all the later reactions 

 suggested by Golgi are suppressed, as it was found that the foregoing- 

 method gave better results and clearer pictures of the network. 



Staining Sections by the Romanowsky Method. J— F. A. McJunkin 

 describes a procedure by which the Romanowsky stain and its modifica- 

 tions may be used for staining sections. The sections are placed in the 

 solution and incubated at 35° for SO minutes, the solution being renewed 

 at the end of 40 minutes. They are then washed in water, and, if quite 

 blue, in 1 :1000 acetic acid until pink ; after this they are immersed in 



2 p.c. tannin solution for 10 to 40 minutes. The tannin is washed off in 

 water, the excess of water removed with blotting-paper, and then the 

 preparation is hurriedly passed through absolute alcohol to xylol, and 

 mounted in balsam. 



(5) Mounting, including- Slides, Preservative Fluids, etc. 



Fixation of Celloidin Sections.§ — D. Carazzi points out that the 

 fixation of thin celloidin sections, of a thickness of 10 ^ or less, to the 

 slide, is a matter of difficulty, and one that requires strict observance of 

 technical details. He gives an account of the Italian method of Brazzola 

 and others, and of the Russian method of Rubaschkin. 



The technique of the Italian method is as follows : The knife is kept 

 moist with 70 p.c. alcohol. The sections as they are cut are transferred 

 to a square piece of thin unglazed paper. They are dried with Swedish 

 filter paper, and then the slide, coated with albumin-glycerin, is applied 

 with gentle pressure. Paper and glass are reversed, douched with 95 p.c. 



* C.R. Soc. Biol. Paris, Ixviii. (1910) pp. 505-7. 

 t Auat. Anzeig., xxxvi. (1910) pp. 207-17 (6 figs.). 

 % Michigan Acad. Sci., 11th Rep., 1909, pp. 110-11. 

 § Zeitschr. wiss. Mikrosk., pp. 533-41. 



