EFFECTS OF DISLOCATION OF EYE UPON GOLDFISH. 63 



the midsaggital line. In the skull and underlying tissue between 

 the left orbit and the drilled hole a narrow channel was cut 

 (including the orbital wall) and thus a communication between 

 the natural and artificial orbit produced. The eyeball was slid 

 along the prepared channel and into the drilled hole, which then 

 served as an artificial orbit. This dislocation can be done very 

 easily and without any force. Neither the eye muscles, nor the 

 nerves of the dislocated eyeball were cut or obviously injured and 

 even the major part of the conjunctiva bulbi and sclerae can be 

 left intact. 



The artificial orbit is able to hold the dislocated eye in place 

 indefinitely. At the replacement the dislocated eye showed some 

 healing in the new orbit. 



The experiment was successful on two animals. In the third 

 fish a fungus infection on the dislocated eye caused death five days 

 after the operation. To prevent such infections a daily po- 

 tassium-permanganate (weak solution) bath of the entire fish is 

 necessary. 



Immediately following the operation (the first one performed 

 on May 15, 1924) no abnormalities in the animal's behavior were 

 observed. After keeping them under observation for a few days 

 the other eye w r as removed (May 20, 1924). We were able thus 

 experimentally to produce real cyclopy. These cyclops in their 

 first week behaved exactly like normal blind fish, they swam and 

 oriented themselves quite as before operation. However, after 

 about the tenth day (in our first protocol: June I, 1924), the 

 animal was observed to tilt the body somewhat to the left. When 

 at rest it assumed a position with its dorsoventral axis several 

 degrees to the left of the vertical. This position was maintained 

 during swimming. 



The tilting of the body toward the side in which the eye was 

 dislocated increased day by day, reaching its maximum in about 

 four weeks (in the case of our first animal: June 27, 1924). This 

 maximum tilting was about 45 and was permanent so long as the 

 eye remained in its new orbit. 



The gross anatomy of the dislocated eye was quite normal. 

 The media were clear. We observed also some oscillatory move- 

 ments of the dislocated eyes, when we took the fish out of water. 



