196 BACTERIOLOGICAL METHODS 



Egg Albumen Medium 

 Whites of two eggs 



Egg albumen peptone (Merck's) i gram 



Distilled water 10° cc.^ 



Prepare as for whole egg medium. If egg yolk bacteria are 

 to be cultured, the following medium may be used: 



Egg Yolk Medium 

 Yolk of two eggs 



Egg albumen peptone (Merck's) i gram 



Distilled water 100 cc. 



Several investigators have reported toxins in eggs. It is 

 also known that some persons are peculiarly susceptible to 

 eggs, being more or less injuriously affected on eating even 

 perfectly fresh eggs. This phenomenon is by some ascribed to 

 personal idiosyncrasy and others suggest that this is due to 

 toxins present to which certain persons are perhaps peculiarly 

 susceptible. The poisonous principles present in eggs should be 

 more carefully investigated. The possibility of toxin forma- 

 tion in cold storage eggs also requires further careful study. 



Eggs decompose very rapidly when the shell and membrane 

 are broken and soon become unlit for use, due to bacterial de- 

 velopment. The shell of the egg serves to prevent, or at least to 

 check, for a time the development of the egg-rotting bacteria 

 through exclasion of oxygen (of the air). It is, however, highly 

 probable that the egg membrane keeps out bacteria even more 

 effectually than does the shell. Shell-less eggs like those of the 

 oviparous snakes are well protected against bacterial infection 

 by the thick membrane, even though the eggs are deposited 

 in the soil and in decaying rubbish. It has also been suggested 

 that the egg membrane contains some bacteriolytic or perhaps 

 bactericidal properties. It is declared, on fairly reliable authority, 

 that fresh egg membrane appUed to buccal inflammations and 

 threatened abscesses will effect a prompt cure. The Chinese 

 have used egg membranes as a medicine for many centuries. 



