522 SUMMARY OF CURRENT RESEARCHES RELATING TO 



(3) Cutting-, including- Imbedding- and Microtomes. 



Dissecting Tile and Stand.* — The tile itself (fig. 74), 6 in. square, 

 half black and half white, is well glazed all over to prevent it soaking up 

 stain, etc., the black being put on before glazing. The stand was devised 

 to meet the demand for a cheap and effective arrangement for class use. 

 The jointed lens-holder has a spring clip to take an ordinary pocket lens 

 and is arranged to slide on a pillar for focusing. A slightly more ex- 

 pensive kind has a drawer for dissect- 

 ing instruments, etc. The tile is 

 made by Flatters and Garnett, Man- 

 chester. 



(4) Staining and Injecting. 



Modification of Neisser's Stain- 

 ing for Diphtheria Bacilli.t — P. 

 FlG 74 Sommerfeld makes films of blood- 



serum or glycerin-agar cultures and 

 stains them with methylen-blue (alcoholic or aqueous or Loeffler's) ; washes 

 with water, dries on blotting-paper, and then treats for a few seconds 

 with a mixture of equal parts of alcohol and formalin. When the pre- 

 paration is almost colourless it is washed and then dried. Smears from 

 diphtheritic membrane require a longer treatment with formalin. The 

 granules are stained dark blue, the bacterial body being pale blue. Con- 

 trast staining, though superfluous, may be effected with vesuvin, chrys- 

 oidin, or eosin. 



New Method of Staining Spores. :£ — A. F. S. Kent recommends 

 the following procedure for demonstrating the presence of spores. A 

 film is prepared and fixed in the usual way. It is then treated with a 

 solution of sodium hydrate for some seconds, after which the still wet 

 film is stained with phenol-fuchsin, heated as usual for a few minutes. 

 The next steps are to decolorise with 25 p.c. hydrochloric acid, wash, 

 counterstain with methylen-blue, then wash, dry, and mount. 



Staining Moist Preparations and Sections by the Azur-eosin 

 Method. § — (I. Griemsa points out some advantages of the application of 

 his staining method to rnobt preparations. By means of this he can 

 demonstrate the minute structure of the nuclei of trypanosomes and 

 halteridia. In dry preparations of amcebas the karyosome in the centre 

 of the nucleus is indicated in a shadowy manner, while in wet prepara- 

 tions it stands out sharp and distinct. This method is also useful for 

 showing the blepharoplast in halteridia, and its relation to the basal 

 portion of the flagelhim. The study of sections and of the minute 

 structure of bacteria is also facilitated by this means. 



New Colour Reaction for certain Albumins. || — W. Arnold has 

 applied the sodium-nitroprusside-ammonia reaction to the investigation 

 of different albumins. The details of the method are as follows : To 

 1 or 2 c.cm. of the albumin solution are added a few drops of a i p.c. 



* Catalogue B, 1910, p. 28. 



t Deutsche Med. Wochenschr., 1910, p. 505. % Lancet, 1910, i. p. 1473. 



§ Centralbl. Bakt., lie Abt. Orig., liv. (1910) pp. 4S9-90. 



|j Bull. Internat. Acad. Sci. Cracovie, 1910, pp. 56-60. 



