168 SUMMAEY OF CURRENT RESEARCHES RELATING TO 



results, and wliich is also very cheap and easy to prepare : Solution I., 

 hfematoxylin 07grm.. absolute alcohol 20 c.ctn. Solution II., alum 

 0'35 grm., distilled water 60 c.cm. The two solutions are mixed and 

 exposed to light in a window for three to fonr days, then 20 drops of 

 tincture of iodine are added and the stain is ready for use. The sections 

 are stained for five to ten minntes and are coloured red-brown. They 

 are then differentiated in 70 p.c. alcohol acidulated with a few drops of 

 acetic acid. The sections then turn blue. This is a good nuclear stain 

 and is recommended for use after fixation with Flemming or any other 

 formula containing osmic acid. 



Relief Staining for Bacteria and Spirochsetes.* — T. H. C. Benians 

 has devised a rapid and simple process to obtain a uniform blue field 

 from which the organisms stand out in sharp relief. The whole pro- 

 cedure occupies only a few moments. A small dro^D of a 2 p.c. aqueous 

 solution of Congo red is placed on a slide and a very small quantity of 

 the bacterial culture or of the exudate to be examined is rubbed into ifc 

 with a platinum wire ; the drop is then spread out into a tolerably thick 

 film either with wire or by means of another glass slide. The film is 

 allowed to dry and then washed over with a 1 p.c. solution of HCl 

 in absolute alcohol. It is dried in the air and is then ready for 

 examination. 



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



Mounting in Fluids.t — W. Cookson makes the following remarks 

 on mounting in fluids : Run a ring of brown cement on the glass slip 

 slightly smaller than the cover-glass to be used, then let dry thoroughly ; 

 build up this ring to the required depth by successive rings, or place on 

 a ring of tin, glass, or vulcanite, and superimpose several rings to the 

 depth of the object to be mounted, taking care that each ring of cement 

 is hard before running another one on. It is better to have a stock of 

 cells of various depths ready in hand. Then ring over the brown 

 cement ring with gum dammar in benzol, using as little as possible, 

 but covering the brown ring evenly ; lay aside for a little while to allow 

 benzol to evaporate until the ring becomes tacky. Place in the centre 

 the object to be mounted, flood with the mounting media, and cover 

 with the cover-glass, breathing on same so that when the cover-glass is 

 dropped slowly on the mount it will not flush out with the superfluous 

 media ; put spring clips on from each end of the slip to the edge of the 

 cover-glass, covering both cover-glass and slip, let this thoroughly 

 harden, and if necessary run another or more rings over this, and then 

 finish as required. 



C6) Miscellaneous. 



Pathogenicity of Giardia (Lamblia) intestinalis.^ — H.B.Fantham 

 and A, Porter have arrived at the following conclusions with regard to 



* Brit. Med. Journ., Nov. 25, 1916, p. 722. 

 t Traus. Manchester Micr. See, 1915, p. 60. 

 t Brit. Med. Journ., ii. (1916) pp. 139-41. 



