In a paper by Capt. Ainley Walker in this Journal1 reference is made to three experiments on three rabbits killed by the “saturation” method of Lieut.-Colonel Gordon which consists in injecting into the auricular vein slope cultures of organisms in massive does at frequent intervals. The organisms used in the present experiments were the Meningococcus, B. typhosus, and Sarcina lutea. Capt. Ainley Walker has handed over to me the organs of the rabbits used for histological examination as to any evidence that might exist of the cause of death. The organs had all been fixed in alcohol. Portions of each were cut out and embedded in the usual way in paraffin. The sections made were stained by haematoxylin and eosin and by such other methods as the appearances suggested. It will be best to set out in detail the features of each organ and then to summarise the whole at the end.