Fig. I. Photograph of six agar plates showing the precipitin reactions of 

 lubrol extracts of microsomes from different rat organs, and the corresponding 

 antisera. The antigen solutions labelled with the same letters in the different plates 

 were aliquots of the same extracts. The extracts were diluted to contain 350-400 

 /xg. protein /ml. T,B,L,K,P,S: microsomal extracts of testis, brain, liver, kidney, 

 pancreas, spleen, respectively; oltn, akm, apm, attn, astn, abm: antisera against 

 microsomes of liver, kidney, pancreas, testis, spleen, brain, respectively. For 

 details see [19]. 



