54 



JACQUES LOEB. 



Kammerer 1 seems to be the only author who still takes it for 

 granted that cave animals owe the degeneration of their eyes to 

 lack of light, and his support for this view consists in the state- 

 ment that five young cave salamanders (Proteus) developed 

 larger eyes under certain (somewhat puzzling) conditions of 

 illumination. In other cases the eyes of Proteus remained 

 unaltered in the light. It would be advisable to make certain 

 whether or not there are two varieties of Proteus and moreover 

 it would be desirable to repeat these experiments on a larger 

 scale. 



The w r riter wishes to publish in this note the results of some 

 experiments made in 1912, which prove that in the fish Fundulus 

 it is comparatively easy to produce embryos with degenerated 

 eyes by various means except by the one Kammerer holds 



FIG. 3. 



responsible for this phenomenon, namely lack of light. The 

 reader may in passing be reminded of the fact that in this form 

 Stockard and later McClendon induced the formation of cyclo- 



1 Kammerer, Arch. f. Rntwicklngsmechn. d. Organ., XXXIII., p. 350, 1912. 



