220 



The Cultivation of Anaerobic Organisms 



his recommendation having recently been revived by Park and made 

 successful for the cultivation of the tetanus bacillus. The paraffin 

 floats upon the surface of the medium, melts during sterilization, 

 but does not mix with it, and "sets" when cool. The inoculation 

 is to be made while the culture medium is warm, after boiling and 

 before the paraffin sets. 



Koch studied the colonies of anaerobic organisms by cultivating 

 them upon a film of gelatin covered by a 

 thin sheet of sterilized mica, by which the 

 air was excluded. 



Salamonsen has made use of a pipet for 

 making anaerobic cultures. It is made 

 of a glass tube a few millimeters in diam- 

 eter, drawn out to a point at each end. 

 The inoculated gelatin or agar-agar is 

 drawn in while liquefied and the ends 

 sealed. The tube, of course, contains no 

 air, and perfect anaerobiosis results. 



Theobald Smith has found the fer- 

 mentation-tube and various modifications 

 of it excellently well adapted to the 

 growth of anaerobes, which, of course, 

 grow only in the closed limb. 



Hens' eggs have been used for anaerobic 

 cultures, and in them the tetanus bacillus 

 grows remarkably well. Conditions of 

 anaerobiosis are, however, not perfect, as 

 can be shown by the behavior of the egg 

 itself. If oxygen be completely shut out 

 by oiling or varnishing the shell, a fertile 

 egg will not develop. 



A quite satisfactory and simple device 

 for routine work with anaerobic organisms 

 has been invented by Wright.* The es- 

 sential feature consists of a pipet, D, with 

 Figs 69, 70. Wright's a ru bber tube, E, at the end, and one in- 

 method of making anaero- . , , , i i_ , i /- 



bic cultures in fluid media terruption connected by a rubber tube, C. 

 (Mallory and Wright). The device will be made clear at once by 



a glance at the accompanying illustration. 



The method of employment is very simple. An ordinary tube of 

 bouillon or other fluid culture- media receives the pipet, the whole 

 being sterilized, the cotton plug in place. The bouillon being in- 

 oculated with the culture or secretion to be studied is drawn up 

 in the bulb of the pipet, A, by suction, until it passes the rubber inter- 

 ruption, C. By forcing the upper end of the pipet downward in the 



* "Jour. Boston Soc. of Med. Sci.," Jan., 1900. 



