ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 109 



staining. In a 60 c.cm. flask 10 drops of methylen-blue solution are 

 mixed with 25 c.cm. of tap-water, and in another flask 15 drops of 

 eosin solution with 25 c.cm. of tap-water. The latter is then poured 

 into the former, after which the blood preparation is immersed in the 

 mixture and kept moving about briskly for about five minutes. On ' 

 removing the preparation water is poured over it to get rid of the super- 

 fluous stain. The preparation is now probably too blue, and the excess 

 is removed by immersing in distilled water. If this be not sufficient, 

 the preparation must be dried and again treated with distilled water. 



The ordinary methylen-blue solution may be used (1 p.c. aqueous 

 methylen-blue med. Hochst with \ p.c. soda), but 1-2 p.c. ammonia 

 or T V P- c - caustic potash are better than the soda. This solution takes 

 4 to 6 weeks to ripen. The eosin solution is a 1 p.c. solution in distilled 

 water. Though the proportion of 10 methylen-blue to 15 eosin was found 

 to be best for most cases, yet when the methylen-blue is weak or unripe, 

 it may be increased to 15-25, and conversely, when too ripe and strong 

 may be reduced to 7-15. 



Demonstration of Flagella in Coccaceas.* — ■ D. Ellis has demon- 

 strated the presence of flagella in a large number of Coccaceaj by the 

 following method. The samples, which were obtained from Krai's 

 laboratory, were sown first on dextrose-agar and Spirillum-agar. As 

 soon as any growth was perceived, a trace thereof was inoculated on 

 fresh agar, and this procedure was repeated until movements in indi- 

 vidual cocci became evident, after which they were re-inoculated and 

 cultivated until a culture was found suitable for flagella preparations. In 

 general A. Meyer's method of fixing and staining (see this Journal, 

 1900, p. 873) was adopted, though modifications in the fixation, length 

 of mordanting, and staining were had recourse to. As a rule, the 

 preparations were fixed for 5 minutes at 40° C, and then mordanted 

 for 4-6 minutes at room temperature. For staining, acid-violet was 

 used ; this was heated until it vaporised, after which the preparation 

 was allowed to stand for 2 minutes at room temperature. 



As the result of the foregoing procedure, the author infers that all 

 species of Coccacece are flagellated. 



Stain for Elastic Fibres.j — J. H. Stebbins, jim., recommends the 

 following method by which elastic fibres are stained dark- blue to blue- 

 black. Dissolve 2 grin, fuchsin and 4 grm. resorcin in 200 c.cm. of 

 boiling water. While boiling add 25 c.cm. of liquor ferri sesquichlorid. 

 and boil for 5 minutes longer ; then cool and filter. Dissolve the pre- 

 cipitate collected on the filter in 200 c.cm. of 94 p.c. alcohol by boiling, 

 and when all is dissolved bring the volume of the fluid up to 200 c.cm. 

 with 94 p.c. alcohol. Finally add 4 c.cm. of HC1, mix well by shaking, 

 and the stain will be ready for use. 



The material may be fixed in Zenker's fluid, or in formaldehyde. 

 The sections are stained for 20 to 60 minutes, washed in absolute alco- 

 hol, cleared in xylol, and then mounted. If desired, they may be pre- 

 viously contrast-stained with carmin. 



* Oentralbl. Bakt., 2" Abi, ix. (1902) pp. 54G-60 (2 pis.), 

 t Journ. N.Y. Micr. Soc, xvi. (1901) pp. 4-5. 



