58 THE BIOLOGICAL BASIS OF INDIVIDUALITY 



to penetrate less readily into necrotic areas in the cartilage than in the rat. On 

 the whole, it is evident that in the mouse the injury and destruction of homoio- 

 genous tissues by the bodyfluids preponderate over the damage inflicted by 

 lymphocytes and connective tissue, and that the activity of the latter may or 

 may not be added to the action of the homoiotoxins of the circulating body- 

 fluids. 



From our observations, it follows that transplantation of thyroid gland, 

 cartilage and fat tissue, together with the associated tissues, cannot serve as 

 accurately as an indicator of the relationship between the individuality differ- 

 entials of host and transplant in mouse as in rat and guinea pig. It is ad- 

 visable wherever possible to use, in addition to these transplants, grafts of 

 ovaries and of striated muscle. A comparison of the effects of transplantation 

 on a combination of these various organs may then serve as a good indicator 

 of the degree of compatibility or incompatibility between the individuality 

 differentials of host and donor. 



