180 THE BIOLOGICAL BASIS OF INDIVIDUALITY 



anterior chamber of the eye is indicated by the fact that heterogenous testes 

 and ovaries survived only up to 20 days, and that at a later date only fibrous 



tissue was found. 



The ovary seems to behave after intra-ocular transplantation in a similar 

 way to the testis (Goodman, as well as Lane and Markee) ; however, the 

 various constituents of this organ are, on the whole, more resistant than those 

 of the testis. In the case of both of these organs, hormones may affect not only 

 the transplants, but the latter also give off hormones which may leave the eye 

 and affect distant organs. In intra-ocular transplants of seminal vesicles and 

 prostate of the rabbit, R. A. Moore and his collaborators have found that the 

 effects of repeated stimulation of the transplants by hormones follow a definite 

 curve; the growth response is strongest in the beginning and then soon 



declines. 



In intra-ocular transplantations of the adrenal gland, conditions are in 

 principle similar to those of the testicle, as a comparison of the results of 

 adrenal transplantations into the eye (Turner) and elsewhere (Wyman and 

 Turn Suden, Atwell, Ingle and Higgins) indicate. Here also, stimulation by 

 the specific anterior pituitary hormone which occurs especially in adrenal- 

 ectomized animals, is important. However, under the more favorable condi- 

 tions existing in the anterior chamber of the eye, cortical glomerulosa tissue 

 may grow, differentiate, and survive for a long time, even in non-adrenalec- 

 tomized animals ; in these experiments, also, the organs of very young animals 

 were used for grafting. But the stimulation by the pituitary hormone in 

 adrenalectomized animals, or the repeated transplantation of pituitary lobes, 

 enhanced the growth and the percentage of survivals. 



Likewise, after intra-ocular transplantation of the hypophysis the grafts 

 remain well preserved. The different types of hypophyseal cells are affected 

 in the usual way by various hormones, and, conversely, transplants of the 

 hypophysis through their own hormones may affect other organs (R. M. 

 May, Haterius, Schweizer and Charipper, Martins) ; but as mentioned pre- 

 viously, pituitary transplants survive for a long time also after subcutaneous 

 transplantation in mice, if the individuality differentials of host and donor 

 are relatively harmonious. 



So far, we have studied only the fate of intra-ocular transplants of tissues 

 which were very young or were derived from litter mates and which had, 

 therefore, special advantages. However, in order to differentiate between the 

 factors which distinguish the reactions against strange individuality differen- 

 tials in the anterior chamber of the eye and in the subcutaneous tissue, it is 

 necessary to transplant into the eye adult tissue and, preferably, thyroid gland. 

 We carried out heterogenous as well as homoiogenous transplantations of rat 

 thyroid, into the eye of the guinea pig. Living homoiogenous thyroid tissue 

 was found at various times from 20 to 50 days after transplantation. There 

 was a diminution of both the intensity of the connective-tissue and the lympho- 

 cytic reaction against the transplant, which for this reason may have shown a 

 slightly better preservation. But neither invasion by fibrous tissue nor lympho- 

 cytic infiltration was entirely lacking in and around these transplants. After 



