REACTIONS TO LIGHT IN VANESSA ANTIOPA 359 



as often toward the blackened eye as toward the normal eye." 

 Similar results have also been obtained with animals in which 

 one eye was injured. Radl ('01, p. 458) extirpated one eye of 

 the water scavenger beetle, Hydrophilus, and found that it de- 

 flected toward the side of the injured eye. Hadley ('08, pp. 

 180-199) seared with a hot needle the surface of one eye of larval 

 lobsters in all stages of development, and maintains (p. 198) : 

 ''The immediate results following this destruction of photo- 

 reception in one eye are: (1) The production of rapid rotations, 

 often at the rate of 150 per ininute on the longitudinal axis of 

 the body, which are invariably in a determined direction. (2) 

 A type of progression in which the larva continually performs 

 'circus movements' or turns toward the side of the injured eye." 

 Since these animals vary in the sign of their reaction to light at 

 different stages of development, it is interesting to note that 

 Hadley maintains that the circus movements made by animals 

 of all ages were all in the direction of the blinded eye. Mast 

 ('10, p. 132) found that " Planaria with one eye removed, either 

 by gouging it out or by cutting off one side of the anterior end 

 obliquely, turn continuously from the wounded side for some 

 time, evidently owing to the stimulation of the wound, since, 

 after this is healed, they tend to turn in the opposite direction." 

 The destruction of the function of one eye is however not 

 always followed by circus movements. Radl ('03, pp. 58-64) 

 states that Calliphora vomitoria is apparently not affected in 

 its behavior by having one eye covered, while Musca domestica, 

 although performing circus movements at times, can also "run 

 rather long distances in one direction." Carpenter ('08, pp. 

 483-491) blackened one eye of Drosophila ampelophila, and 

 reported that now and then one performed circus movements, 

 but he says (p. 486), "This conduct was exceptional, and was 

 never persisted in except in the case of a single insect which had 

 long been active and showed signs of fatigue." They usually, 

 howe^^er, deflected somewhat toward the functional eye as they 

 proceeded toward the light. To quote further (p. 486), "They 

 crept in a fairly direct path toward the light, although a ten- 

 dency to deviate toward the side of the normal eye regularly 



