REACTIONS TO LIGHT IN VANESSA ANTIOPA 361 



several weeks in an aquarium, it never moved in a strai?:ht line, 

 but always in a course curved toward the side of the injured eye. 

 He says ('01, p. 458) : ''Es hat darnach noch mehrere Wochen in 

 meinem Aquarium gelebt, bewegte sich aber niemals gerade 

 sondern immer nur in einem Bogen concav nach der Seite des 

 extirpirten Auges." This investigator ('03, p. 62) also observed 

 a fly, Dexia carinifrons, on the second day after its eye was 

 blackened and found its behavior was similar to that exhibited 

 im]nediately after the eye was covered, that is, it moved con- 

 tinually toward the functional eye. 



The second group of experiments, as previously stated, refer 

 to insects with one antenna removed. V. L. Kellogg ('07, pp. 

 152-154) removed the left antenna from a male silk worm moth, 

 and found that when such an animal was placed three or four 

 inches from a female it '4noved energetically around in repeated 

 circles to the right, or, rather, in a flat spiral, thus getting (usually) 

 gradually nearer and nearer to the female." Males with the 

 right antenna removed turned continually to the left. In the 

 same year, Barrows ('07, pp. 515-537) removed the terminal 

 segment from one antenna of some fruit flies, Drosophila ampelo- 

 phila, and then, after twenty-four hours without food exposed 

 them to the odor of fermenting banana. He maintains that they 

 moved in circles toward the uninjured antenna in all but a few 

 cases in which they deflected in the opposite direction. 



The third group of experiments mentioned comprises those in 

 which parts of the brain and inner ear have been injured or 

 removed. In these cases it is also maintained that the animals 

 make circus movements. 



It can thus be seen that great diversity exists among the results 

 obtained by the various investigators in their experiments on 

 animals with the sense organs on one side destroyed. Among 

 these, those which refer to the eyes are of greatest immediate 

 interest to us. In these experiments it was found that while 

 photo-positive animals usually turn toward the functional eye 

 and photo-negative animals toward the non-functional eye, some 

 turn in the opposite direction and others orient fairly accurately, 



THE JOURNAL OP EXPERIMKNT AL ZOOLOGY, VOL. 20, NO. .3 



