1566 Journal of Applied Microscopy 



Method for Rearing Amoeba. 



It is frequently very difficult to secure a large number of Amoebaj satisfactory 

 for class work when wanted. The usual method of visiting the pools of stagnant 

 water is very uncertain and laboratory cultures made from dacaying Algae are 

 equally unsatisfactory. For some time the writer has been experimenting with 

 protozoan cultures and has been successful in securing Amoebae in the following 

 simple manner : A nutrient medium is made by boiling a lot of dead leaves. 

 As soon as cool, both liquid and leaves are placed in an ordinary battery jar 

 and a lot of unboiled leaves and enough water to stand about one inch above 

 the leaves added. In two or three days a scum will form and in from five to 

 ten days, depending upon the temperature of the room, Amcebae will be found in 

 the scum in large numbers. They will be small, but very satisfactory for class 

 work. The writer has tried this method a great many times, and in different 

 localities and at different seasons of the year, and always been successful. 

 De Pauw University, Greencastle, Indiana. Mel T. Cook. 



The Arrangement of Cilia on Paramecium. 



The cilia of many of the Infusoria are so fine and so closely set, notably on 

 Paramecium, that it is very difficult for the student to determine their exact 

 arrangement. Careful focusing will sometimes reveal their order on favorable 

 specimens, but the use of Loeffler's alkaline methylen blue as a stain has been 

 found to be a very reliable method of demonstrating their arrangement on 

 almost every specimen. A drop of the stain is mixed with the drop of water in 

 which the animalcules are swimming on the slide and the cover glass placed in 

 position. Intra vitam staining takes place in many of the individuals, but they 

 soon die and the cuticle separates more or less completely from the cytoplasm 

 and forms a halo around the deeply stained body. The perforations in the cu- 

 ticle are thus brought very distinctly into view and the plan of arrangement of 

 the cilia revealed. The stain is prepared as follows : Add 8(1 c.c. of a concen- 

 trated alcoholic (05 per cent.) solution of methylen blue to 100 c.c. of a .0001 

 solution of caustic potash. The caustic potash solution may be prepared by 

 adding 1 c.c. of a one per cent, solution of potash to 100 c.c. of distilled water. 

 University of Rochester. CharlES Wright Dt)J)(;E. 



Labeling Mounted Specimens. — The following method is given as useful 

 where specimens mounted on cover-glasses or slides are to be passed through 

 various solutions : Mix with equal parts of ^^g albumen and glycerin, sufficient 

 lampblack to make a good black fluid. This may be used with a steel pen for 

 writing on the glass, after which the glass should be held over a flame until the 

 characters are dry. The markings are not removed when the specimens are 

 passed through solutions. — Knmvledge, 24 : 191. 



