754 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Fixing of Stains by Bacteria.* — G. Peju and H. Rajat experi- 

 menting on the staining properties of various bacteria during life with a 

 number of different staining reagents, find that these latter may be 

 considered in three groups. Firstly, those stains that colour the 

 medium, often intensely, but leave the colour of the culture unaffected, 

 and which includes carmin, fuchsiu, hematein, hematoxylin, blue-azur, 

 malachite-green, etc. Secondly, those stains that colour the medium and 

 culture alike, and includes eosin, methylen-blue, neutral-red, Merck -red, 

 picric acid, heliantin, etc. Thirdly, those stains that are taken up by 

 the bacteria, the medium being decolorised. 



RoTHiG, P. — Wechselbeziehung zwischen metachromisclier Kern- und Protoplasma- 

 farbung der Ganglienzelle und dem Wassergehalt alcoholischen Hamotoxylin 

 Eosungen. Parts 2 and 3. (For Part 1 see this Journal, 1907, p. 110.) 



Zeitsclir. iviss. Mikrosk., xxiv. (1907) pp. 109-28. 



(6) Miscellaneous. 



Detection of Bilharzia Ova in Urine and FaBces.j — T. Mazzei 

 finds that the following procedure gives better results than the methods 

 usually adopted. The sediment of the urine or of the diluted ffeces is 

 spread out on slides, and the thickish and extensive layer dried at a 

 gentle heat until all the water is evaporated. The preparation is then 

 washed for 5-10 minutes in an aqueous 3 p.c. solution of hydrochloric 

 acid, and examined under a low power to see if all the salts have been 

 dissolved out. They are then washed for 5-10 minutes in a 30 p.c. 

 solution of caustic soda or potash, in order to get rid of the mucus and 

 other organic elements. The films are then dried with gentle heat and 

 after this may be examined under the Microscope to ascertain if any 

 parasites are present. It is sometimes better to stain the preparation 

 with borax methylen-blue, and afterwards differentiate with 1 p.c. 

 hydrochloric acid. Instead of methylen other pigments may be used, 

 such as carbol-thionin or Ehrlich's hiematoxyhn. 



Microscopic Study of Pen and Ink Lines.j — M. D. Ewell finds 

 that the serrations in ink and pencil lines are due to irregularities in the 

 surface of the paper itself. By making very thin films on glass witli 

 carbon from a smoky flame, or with a solution of wax and asphaltum in 

 benzol, and writing thereon with the dry steel pen, it was found, on 

 examination under a power of over 120 diameters, that the lines were 

 clear, sharp, and free from serrations of any sort. The ordinary writing 

 of the same persons on paper with pen and ink had previously shown 

 abundant serrations. Other explanations of the phenomenon are that 

 the inequalities are due to variations of nerve force or to pulsations 

 from the vascular system. 



Errera's Practical Course of Vegetable Micro-chemistry.§ — By 

 micro-chemistry the writer of this little treatise means the localisation 

 of substances in plants, " microscopical topo-chemistry." The booklet 

 consists of the notes used by Leo Errera in the practical course of 



* C.R. Soc. Biol. Paris, Ixii. (1907) p. 954. 

 ■ + Riforma Medica Ann., xxi. No. 24. 

 X Trans. Amer. Micr. Soc, xxvii. (1907) pp. 21-3. § Bruges, 1906, 24 pp. 



