208 



SUMMAKY OF CURRENT RESEARCHES RELATING TO 



prism, covering half of the aperture, is furnished with the instrument ; 

 but any other form of illuminator may be used, if preferred. 



Fig. 29. 



B. Technique.* 

 (1) Collecting: Objects, including- Culture Processes. 



Culture of Mycetozoa. — A. Lister f gives some useful hints in 

 respect to the cultivation of various species of Mycetozoa from spores 

 for the purpose of following the whole cycle of development. 



Clara Langenbeck J describes a convenient method of cultivating the 

 plasmodes of Mycetozoa in an infusion of hay. 



Medium for the Bacteriological Examination of Water.§ — Dr. J. 

 Thomann, after an examination of various nutrient media for the 

 bacteriological examination of water, advocates the following, which 

 constantly gave the best results. Liebig's meat extract 6 grm., pepton 

 Witte 10 grm., salt 5 grm., diphosphate of potassium 2 grm., are 

 dissolved in 1000 grm. of distilled water in a water-bath, and to the 

 solution 100 to 120 grm. (according to the time of year) of gelatin are 

 added. When the gelatin has dissolved, the mixture is neutralised with 

 normal caustic soda solution, blue litmus paper being used as indicator, 

 and then to the neutral fluid 1-5 grm. of soda ( = 15 ccm. of 10 p.c 

 soda solution) are added. After boiling for half an hour in a steamer, 



* This subdivision contains (1) Collecting Objects, including Culture Pro- 

 cesses ; (2) Preparing Objects ; (3) Cutting, including Imbedding and Microtomes ; 

 (4) Staining and Injecting ; (5) Mounting, including slides, preservative fluids, &c. ; 

 (6) Miscellaneous. 



t Journ. of Bot., xxxix. (1901) pp. 5-8. 



X Journ. Applied Microscopy, iv. (J 901) pp. 1119-21 (3 figs.). 



§ Centralbl. Bakt., vi. (1900) pp. 796-800. 



