ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



Ill 



(5) Mounting-, including Slides, Preser«rative Fluids, &c. 



Filter Bottle for Mounting Fluids.— H. Taverner exhibited at the 

 November Meeting, 11)06, a small filter bottle (fig. 2i>), the special 

 advantage of which is that volatile micro-mounting 

 fluids can be filtered with or without heat, and 

 without alteration in strength, as any vapour that 

 may be given off is retained in the bottle. The 

 apparatus consists of a bottle-shaped funnel which 

 fits like a stopper into the neck of the lower bottle. 

 In this funnel-stopper a tube is placed, and the 

 surrounding space firmly packed with cotton or 

 glass wool. The fluid to be filtered is placed m 

 the upper bottle, care being taken that it does not 

 reach the top of the tube, which is for the purpose 

 of allowing the air or vapour to pass from the lower 

 to the upper bottle during filtration. The filter 

 has been used for glycerin jelly, glycerin solutions, 

 celluloid varnish, celloidin, benzol, balsam, etc. 



(6) Miscellaneous. 



Method for Differentiating Bloods.* — Pior- 

 kowski, following on his observations that ox serum 

 causes a coagulum with cow's milk, but with 

 woman's milk has no reaction, finds that when 

 hydrocele fluid, ascitic fluid, or human serum, is 

 treated with human blood, after half an hour a red 

 deposit occurs, a clot forms and the supernatant fluid remains clear ; 

 other varieties of blood are dissolved in the human fluid. Using the 

 sera of horses, cattle, and other animals, it was found that homologous 

 bloods were coagulated, heterogenous bloods were dissolved. 



Improved Methods for Recognition of Blood and Seminal Stains.t 

 E. H. Hankin has found that if a blood stain has been altered by putre- 

 faction or drying it may, nevertheless, give the absorption bands of 

 hgemochromogen, even although the blood-colouring matter is in an 

 apparently undissolved and insoluble condition. The suspected stain is 

 cut out and plunged into boiling water for a few moments. It is then 

 placed on a slide and wetted with ammonium sulphide. It is examined 

 under the microscope and the specimen is moved until the whole field of 

 view is occupied by a portion of the coloured material. If this cannot 

 be achieved with a low power the use of an oil immersion may be necessary. 

 The eye-piece is then taken out and replaced by a microspectroscope. 

 If the stain is of blood the two absorption bands of haemochromogen 

 will be seen. Should the bands not be visible, as may occur apparently 

 owing to the effects of putrefaction, a drop of 10 p.c. solution of potassium 

 cyanide should be allowed to fall on the stain. Two bands will at once 

 develop resembling those of haemochromogen, but situated a little nearer 

 to the red eud of the spectrum. 



Half actual size. 

 Fig. 23. 



* Centralbl. Bakt., Ref., xxxviii. (1906) p. 752. 

 t Brit. Med. Joum. (1906) ii., pp. 1261 and 1843. 



