ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



107 



Microscope stand. It has a double dark slide and a lens for fine adjust- 

 ment. The size of the image is 9 by 12 cm., and the bellows have an 



extension of 50 cm. 



B. Technique.* 



%» 



f 



.tnumummiMMmw 



agate^ ^r 



• .l - ni)lht? rr-rS ' 



Fig. 30. 



(.13 Collecting: Objects, including- Culture Processes. 



Does Anthrax form Spores under Anaerobic Conditions? — K. 

 Slupski \ answers the question whether anthrax when cultivated under 

 strictly anaerobic conditions forms spores, in the negative. The method 

 adopted and the apparatus used are as follows. The essential feature 

 in the apparatus is a glass pan with a broad lip (fig. 30, c). . This pan, 

 which is 15 cm. in diameter, 5 cm. high, and the breadth of the lip 

 1JL cm., is placed inside another glass pan upon the bottom of which are 

 two dishes a and b. The dish a is for pyrogallic acid, the dish & for 

 distilled water. Over the dish a is 

 placed a glass tripod the legs of 

 which rest in b. Upon the tripod is 

 placed a double layer of blotting 

 paper, and on -this rests an open Petri 

 capsule. One half of the agar plate 

 in the Petri capsule is inoculated 

 with anthrax blood and the other with 

 tetanus. As tetanus is an essential anaerobe its growth affords an excellent 

 criterion of the fulfilment of anaerobic conditions. Alter the plato is 

 inoculated two bits of caustic potash (about 14 grm.) are placed in the 

 pyrogallic acid (about 25 grin.) over which has been poured some 

 25 ccm. of warm distilled water. The various parts of the apparatus 

 haviDg been adjusted, warm paraffin is poured into the outer jar to form 

 a layer of 3-4 cm. high ; and when this has cooled and set another 

 layer of liquid paraffin. This done, the whole apparatus is removed for 

 40-50 hours to a refrigerator at a temperature of 5-6° C. This is to 

 prevent the growth of anthrax while the oxygen is being absorbed. 

 The final step is to incubate for 70-80 hours at 37°. 



Methods for Rearing Amoebae. J — M. T. Cook makes a medium by 

 boiling dead leaves. When cool, liquid and leaves are placed in ajar 

 and unboiled leaves and enough water to stand about 1 in. above the 

 leaves added. In 2 or 3 days scum forms, and in from 5-10 days, according 

 to the temperature, amoebae will be found in the scum in large numbers. 

 They are small but very satisfactory for class purposes. 



Yeast-Water for Biological Analysis.§— H. Will recommends the 

 use of yeast-water rendered alkaline by the addition of ammonia for 

 bacteriological purposes. 8-10 ccm. of neutral perfectly clear yeast 



* 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 elides, preservative fluids, &c. ; 

 (6) Miscellaneous. 



t Centralbl. l'nkt., l ,e Abt., xxx. (1001) pp. 396-400 (2 figs.). 



t Journ. Applied Microscopy, iv. (190J) p. 1566. 



§ Zeitschr. ges. Brauwcsen, xxiv. (1901) pp. 289-91. See Centralbl. Bakt., 

 2 !i Abt., vii. (1901) pp. 8i>2-3. 



