No. 647] AUTOPHORIC TRANSPLANTATION 553 



In the new-born rat, as in many mammals, the eyes are 

 tightly closed and the lids connected by tissue. This 

 seemed to afford favorable conditions for the exchange 

 of eyes, as they would be kept in place by the tight closure 

 of the eyelids. Having severed the lids, I interchanged 

 the eyes and, as expected, the eyelids shut again tightly 

 and kept the eyeballs in place. But when the eyelids 

 opened again at the normal time, the eyes had grown on, 

 although they were not functional, and totally disap- 

 peared in time. Disappointed at this failure, the experi- 

 ments were discontinued. It is now pretty certain that 

 this poor result was due to the unfavorable conditions 

 obtaining in very young mammals, for we are now able 

 to demonstrate the correctness of my original supposi- 

 tion. Theodor Koppanyi, a young Hungarian student, 

 working under my direction in the " Biologische Ver- 

 suchsanstalt " in Vienna, has succeeded in making the 

 autophoric transplantation of the eye in a variety of 

 species, extending from fish to mammal. The work of 

 Pardo on Triton was confirmed, and older rats yielded 

 excellent results. It seems that in the young stages of 

 rats there were difficulties in the way of the eye obtaining 

 a sufficient supply of blood, since also in Koppanyi 's ex- 

 porimonts it was far easier to get the eyes to become 

 roattnclu'd and t'liuctional in o\dov specimens. 



Ih.UmmI, it is probabh^ that the i^ressure of the eyelids 

 exerti'd on the i'i'i)laeed eyol)alI in the new-born rats is a 

 hindrance. Grown rats do not close the eyelids tightly 

 upon the eyeballs, so that it is even advisable to pin the 

 lids or sew them together for a day or two, lest the ani- 

 mal whisk out the implanted eyes or scratch at them be- 

 fore they are attached sufficiently firmly to withstand such 

 treatment. 



We have been able to show that these r-e])lanted eyes 

 are functional, all possible tests yielding positive results 

 and being in striking contrast to those in blinded ani- 

 mals.' Microscopical examination of sections through 



