No. 642] SEROLOGICAL REACTIONS 



91 



directly from a common source, presmiial)ly lioariim- in 

 their chromosomes samples of all the cliroiin.-oiiial mm- 

 ponents of the original zygote, is it iinrca-oiial)!.- in -ap- 

 pose that if changes come to pass which can affect certain 

 constituents of tissue-cells, this influence, if borne in the 

 circulating fluids of the body, could also affect the ho- 

 mologous constituents of the germ-cells I Personally, I 

 think that such a hypothesis is not unreasonable. But is 

 there even the least bit of evidence on this point? I 

 believe that there is. I feel that in the transmission 

 of eye-defects secured by Dr. E. A. Smith and myself in 

 fetal rabbits by means of serum immunized against rabbit 

 crystalline lens, we have a bona fide case of such parallel 

 influences. Since I have already presented the facts 

 before this Society and inasmuch as the details are avail- 

 able in printed form,^ I need not repeat them now. It is 

 sufficient to recall to you that we secured a fowl-serum 

 immunized against rabbit crystalline lens which when 

 injected into pregnant rabbits penetrated the placenta 

 and occasionally attacked the lens of the fetal young, 

 the outcome being marked eye-anomalies in such young. 

 Since, once produced, the defcM'ts wore transmitted to 

 successive generations throiiuli Ix.tli male and t'eiuale 

 lines, we interpreted our results to mean that the imminie 

 serum was not only specifically cytolytic for the newly 

 forming lens-tissue of the fetus, but that it also attacked 

 the representatives of such tissue— its genes, if you please 

 — .in at least some of the germ-cells of the fetus. If true, 

 this must mean that ther(^ is «m\e degree of constitutional 

 identity, probably pi'otein linmolouy, between the mature 

 substance of a tissue and it - cdrr.'latix-e in the gtM'ni. And 

 in view of the fact tiiat, !.a-i<-allv. inheritane,. i- mainly 

 a question of the iieriietualion of -neeilie pi-Dtein-eom- 

 plexes, and develo])m.'nt. the iv-nlt of di ff<'rential reac- 

 tions of these same fund:;m.-ntal eonstituetit- nii.ler dif- 

 fering conditions of eii\ i romnent. is thi- an nnrrasoiiablfe 

 inference? 



But does anytliing .-onii-afahie to thi^ omir hi the 

 ordinary course of animal exi-teiiee.' Do (•\t(»l\-!n> or 

 kindred substances wldeli <-an modify oi- deMmy hotli 



