Resorption of albuminoid fluids 121 



of the receptors which are combined with the haptophore groups of 

 the ichthyotoxin. As these receptors fulfil an important function in 

 the nutrition of the red corpuscles, the latter reproduce them in larger 

 numbers than were originally present. We know that in the pheno- 

 mena of repair an over-production of the new-formed parts often 

 takes place and, according to Ehrlich, to this over-production the pre- 

 sence of antitoxins in the fluids of the body is due. The receptors, 

 developed in excess by the red corpuscles, fill these cells, and no 

 longer finding room therein are extruded from them and overflow 

 into the blood and other fluids of the organism. When a fresh injec- 

 tion of toxin makes its way to the blood it there meets with a number 

 of free receptors, endowed with an affinity for the haptophore group 

 of the molecule of the toxic substance. The chemical combination 

 between the two substances takes place at once in the plasmas, a fact 

 which prevents the haptophore group of the toxin from uniting with 

 the receptor of the red corpuscles and so injuring these cells by in- 

 troducing the toxophore group into them. According to this theory 

 the same receptors which, in the free state in the fluids, fulfil the 

 antitoxic function become in the interior of the red corpuscles the 

 vehicles of intoxication and consequently fulfil a philotoxic function. 

 This opposite role of the receptors has often been compared to a 

 lightning-conductor; so long as the receptors are attached to the 

 molecule of the living protoplasm they attract the toxin just as a 

 lightning-conductor attracts the lightning when it is badly insulated. 

 So interpreted, it is easy to conceive that the red corpuscles of 

 animals whose fluids are antihaemotoxic may be sensitive to the 

 toxic action of eel's serum, as has been observed by Tchistovitch. As 

 soon as the protective fluids have been removed from the red cor- 

 puscles of the immunised organism, the corpuscles when placed in 

 contact with ichthyotoxin (eel's serum) attract the haptophore groups 

 of the poison by means of their numerous receptors. These hapto- 

 phores in their turn introduce the toxophore groups which dissolve 

 the red corpuscles without the slightest difficulty. This theory does 

 not explain the cases, which are numerous, in which the red corpuscles 

 of rabbits that are vaccinated against eel's poison resist this poison. 

 Camus, Gley, and Kossel, working independently, have arrived at the 

 result that the red corpuscles of immunised rabbits, from which the 

 serum has been carefully removed, are not dissolved when submitted 

 to the action of ichthyotoxin, whilst the red corpuscles of untreated 

 rabbits placed under the same conditions, undergo a rapid solution. 



