648 SUMMARY OF CURRENT RESEARCHES RELATING TO 



when cultivated in neutral red-grape-sugar agar in from 24-48 hours. 

 The medium is composed of 100 ccm. fluid agar, 0*3 grm. grape sugar, 

 1 ccm. saturated aqueous solution of neutral red. 



Romanowski's Stain for Bacteria. * — Prof. Zettnow gives the 

 following information as to his modification of Romanowski's method 

 of staining bacteria. f 50 ccm. of 1 per cent, solution Hochst's medicinal 

 methylen-blue are mixed with 3-4 ccm. of 5 per cent, solution of crystal- 

 lised soda. The mixture is ready for use in 2-3 weeks. The eosin stain 

 is a 1 per cent, solution Hochst's eosin B.A. When required for use, 

 1 ccm. of the eosin solution is added drop by drop to 2 ccm. of the blue 

 solution, and the mixture kept well stirred the while. 



Some of the mixture is poured or pipetted on to the cover-glass 

 films and allowed to act for 5. minutes. The preparation is then 

 washed in water and inspected in this under the Microscope, after which 

 it is differentiated with eosin, &c. These preparations when mounted 

 in balsam keep better than might be anticipated. 



Modification of Romanowski's Stain for Bacteria.}— Dr. Feinberg 

 recommends the following modification of Romanowski's method for 

 staining bacteria. The films are air-dried and fixed in absolute alcohol 

 f or l_i hour. They are then stained in a mixture made by heating 

 1*5-2 per cent, solution of methylen-blue to 70°-80° C. on several 

 successive days, to get rid of the red pigment in the methylen-blue. 

 To 1 ccm. of this solution 4-6 ccm. of 1 per thousand eosin solution are 

 added. The cover-glasses are immersed in the mixed eosin-blue solu- 

 tion for 20 minutes, and on removal are washed with water. They are 

 next decolorised in absolute alcohol. This takes some minutes. In 

 successful preparations the nucleus is red and the plasma blue. The 

 nuclear division in diphtheria bacilli is specially well seen by this 

 method. 



New [Method for Staining Fibrin.§ — Prof. Kockel adopts the 

 following procedure for staining fibrin. The sections are stuck on 

 with albumen-glycerin, and when freed from paraffin are immersed for 

 5-10 minutes in 1-5 per cent, chromic acid solution. After washing 

 they are stained for 15-20 minutes with Weigert's hematoxylin. They 

 are again washed and then immersed in 1 per cent, alum solution until 

 they become dark blue. After washing, the sections are differentiated 

 in Weigert's ferridcyanide solution, and then washed again. Next, they 

 are transferred to a saturated solution of alum for 15 minutes to 1 hour. 

 After washing they are contrast-stained with carmin or safranin, and 

 having been dehydrated are passed through clove oil or xylol and mounted 

 in balsam. The fibrin is dark blue to bluish-black. 



New^ Method of "Staining- Actinomyces. ||— Dr. A. Sata gives the 

 following method for staining Actinomyces in sections. The pieces are 

 fixed in formalin solution and the sections stained with a dilute 

 hematoxylin solution. The sections are then immersed in alcohol for 



i 



* Centra lbl. Bakt. u. Par., l te Abt , xxvii. (1900) pp. 803-5. 



t See this Journal, 1809, p. 664. 



X Deutsche Med. Wochenschr., xxvi. (1900) pp. 256-7. 



§ Centralbl. f. allgem. Pathol, u. pathol. Auat, x. (1899) pp. 749-57. 



|| Op. cii, xi. (1900) pp. 101-2. 



