Journal of Applied Microscopy. 271 



should be ground vertically and the top and bottom should have exactly the 

 same diameter. A rubber band can then be slipped over the circumference of 

 the two flanges, thus materially assisting in closing the apparatus. The 

 unground surface of the flanges should be parallel or nearly so in order that the 

 clamps will not slip off. 



The gelatin or agar Petri dishes are placed in the lower jar. It is unneces- 

 sary and undesirable to remove the tops. The ground surfaces of the apparatus 

 should be lubricated with a mixture of beeswax and olive oil (1:4). The upper 

 part is then placed in position and the wide rubber band is slipped over the 

 circumference. Three clamps (No. 1 amateur vise, Phoenix Hardware Co., 

 Phcenix, N. Y.) are applied to the flanges. A slit piece of rubber tubing should 

 be slipped over the jaws of the clamps. Hydrogen is then passed through the 

 apparatus in the manner described above. Finally the stopper is turned and the 

 apparatus can then be set aside for the organisms to develop. 



In this way colonies of the anaerobic bacteria can be obtained with the 

 greatest ease, and what is important, they are accessible for observation and trans- 

 plantation. The pyrogallate method can be used with equally good results. 

 Three to five grains of pyrogallic acid are placed in a dish which is about 10 

 cm. in diameter and 8 cm. high. This is placed on the bottom of the lower jar 

 and covered with a strip of glass about 5 cm. wide. The Petri dishes are then 

 stacked on top. The upper half of the apparatus is placed in a position so that 

 only a narrow slit remains open. By means of a pipette or other arrangement 

 •J5 cc. of concentrated potash solution (1:4) are added as rapidly as possible. 

 The top is then closed completely and the rubber band and clamps applied as 

 before. 

 Hygienic Laboratory, University of Michigan. 



A Biological Society has been organized at De Pauw University, with a lim- 

 ited membership of twenty-five composed of advanced students of the university. 

 The membership in this society is based on merit of students. Prof. Mel. T. 

 Cook will soon publish a thesis on the water lily. h. h. z. 



At a recent meeting of the board of managers of the New York Botanical 

 (jarden. Dr. D. T. MacDougal, professor of physiology in the University of 

 Minnesota, was appointed to fill the newly created position of director of the lab- 

 oratories. Dr. MacDougal has accepted the appointment, and has handed his 

 resignation to the president of the University of Minnesota, to take effect July 

 1st, when he will assume his new duties in New York. 



