540 THE BIOLOGICAL BASIS OF INDIVIDUALITY 



Witebsky found that the globulin of adrenal glands and pancreas lose their 

 organismal differentials as the result of the heating but retain their organ 

 differentials. 



4. If we use whole cells or pieces of organs for immunization, we find 

 again a combination of organ and organismal differentials present in the 

 material serving as antigens. If rat leucocytes are injected into an animal 

 belonging to a different species, the immune serum reacts most strongly with 

 rat leucocytes and more weakly with kidney and liver of rat. This indicates 

 a relative organ-specificity ; but in addition there is noticeable also a reaction 

 with guinea pig and rabbit leucocytes, which is weaker, however, than the 

 reaction against rat leucocytes. This graded character in the reactions indicates 

 the presence of organismal differentials. Forssman differentials are also 

 found in leucocytes (Witebsky). 



5. In the lens there seem to be only organ-specific differentials, yet a 

 closer analysis indicates the presence also of organismal differentials. This 

 was shown by the transplantation experiments of Fleisher, and the recent 

 experiments of Blumenthal indicate even the presence of individuality dif- 

 ferentials. Serological tests also suggest the presence of organismal differ- 

 entials, at least of the very coarse ones. Thus immune serum against mam- 

 malian lens manifests a weaker reaction against fish lens, or the reaction 

 against the latter may even be lacking altogether. Conversely, the anti-fish 

 lens serum reacts more strongly with fish lens than with mammalian lens 

 (Hektoen and Schulhof). By means of absorption tests it can be shown 

 that each type of lens, fish as well as mammalian, binds its own immune 

 serum quota in a specific manner and leaves the other fraction behind in the 

 serum. 



According to Krusius, a guinea pig sensitized against a mammalian lens 

 reacts only very weakly against fish lens, and not at all against the lens of 

 the eye of cephalopods. Likewise, the observation of Krusius, that if animals 

 are sensitized with the complete lens of a certain species, there may take 

 place a slight reaction also with the serum from this species, indicates the 

 presence of organismal differentials. As Krusius points out, this reaction is 

 probably due to the effect of the outer layer of the lens, which shows as yet a 

 less fargoing tissue differentiation than the inner lens fiber material. With 

 increasing tissue differentiation of this, as well as of other organs, the 

 organismal differentials seem to become less marked or to disappear in the 

 end, while the organ differentials become more pronounced, at least as far 

 as the serological tests indicate. It is the transformation of the capsular 

 epithelium into lens fibers which brings about this change. A similar change 

 takes place, according to Krusius, when the epidermis undergoes keratiniza- 

 tion. The species-specificity depends, therefore, apparently upon the presence 

 of primary tissue proteins, while the organ-specificity depends upon a modi- 

 fication of the primary tissue proteins comparable to the introduction of a 

 N0 2 group into the protein molecule in the experiments of Obermayer and 

 Pick. The keratin of horse hoof and of human hair shows accordingly, in 

 anaphylaxis experiments, an organ-specificity in addition to a species- 



