A diagnostic dey for identifying organisms recovered from rotten eggs

A collection of 119 cultures of bacteria was assembled from eggs which had rotted on the premises of producers. All but 13 of the isolates were Gram‐negative. These were characterised in detail and the data used (i) to devise a determinative key that permits rot‐producing bacteria to be identified at generic level, and (it) to establish systems whereby identification at species level can be achieved with the minimum of tests. With the use of these schemes the following were recognised: Pseudomonas fluorescens, Pseudomonas maltophilia, Aeromonas liquefaciens, and members of Flavobacterium, Cytophaga, Proteus, Escherichia, Hafnia and Aerobacter. The literature dealing with the microbiology of rotten eggs was reviewed with the object of assessing the incidence of the organisms listed above in rotten eggs of commercial origin.