558 THE AMERICAN NATURALIST [Vol. LVI 



{a) equal size and orientation; {h) simple exchange with- 

 out exertion of pressure or additional injury to the nerve 

 beyond a clean cut; (c) prevention of loss by the natural 

 means of the animal itself (friction, clasp, blood clot). 



2. By this method of " autophoric " or " self-retain- 

 ing " transplantation, the graft taken from an adult in- 

 dividual and replanted into another may be restored to 

 function, even the nerves of the head reuniting, and the 

 bearer being repaired in every respect. 



3. These achievements are in accord with the theory 

 stating regeneration to be nothing else than the accelera- 

 tion of physiological processes going on all the time in 

 the body of organisms, for it can be demonstrated that 

 the reattachment proceeds in the same sense as the first 

 growth of the nerve. They contradict, however, the gen- 

 eral assumption that the maintenance and functional re- 

 generation of organs are dependent on their uninter- 

 rupted connection with their special nervous center. 



4. Till now we have been able to obtain autophoric 

 replantation with restoration of function in the visceral 

 sac of Antedon (Echinoderms— Pr^ifcmm, 190.1), in the 

 eyes of fish, amphibia and mammals (Vertebrates— -fiTo^- 

 pdnyi, 1921), in the lens of the two former classes {Wies- 

 ner, 1921), in the heads of insects, walking sticks, water 

 bugs, water beetles (Insects— FiwfeZer, 1921) and in other 

 cases not yet ready for publication. 



5. Experiments with larval stages of amphibia and in- 

 sects as compared with the imaginal state of the same 

 species show that there is no radical difference as to the 

 restoration of function after excision and replantation of 

 a part, in mammals (rats) grown-up specimens even 

 seeming to be more favorable for autophoric replanta- 

 tion. 



LIST OF EEFEKENCES 

 Boeke. Studien zur Nervenregeneration, I. Verhandl. Ron. Alcad. van 



Wetensch. te Amsterdam, 2. Sekt. Deel XVIII, 1916; II. XIX, 1917, 

 Cajal, Ramon y. Studies sobre la Degeneracion y Eegeneraci6n del 



sistema nervioao. Madrid, Hijoa de NicoWs moya, I, 191S, 11, 1914. 

 Finkler, W. Kopftransplantation bei Insecten, I. Funktionsfahigkeit 



