(1) The cytotoxins are not specific.
(2) The changes occurring after the injection of different cytotoxins are similar and do not vary in kind.
(3) The changes do, however, vary in degree in the following order, the one having the most marked effect being placed first, etc.:
(4) Nephrotoxin causes the most specific change.
(5) The hæmolymph glands play some important part in the production of eosinophiles. The hæmolytic action of hæmolymphotoxic serum is greater than that of other cytotoxic sera.
(6) The histological changes which are observed in every case are secondary to the hæmolytic factor present in all cytotoxic sera.