FUNCTION OF VIBRISSAE IN BEHAVIOR OF WHITE RAT 63 



G. Records of the Experiments of Second Series — June 11 to Oct. 18, 1911 



(e) Normal rats with vibrissae— (5 rats) : 



Average number of trials in learning, 161. 

 Average time of the last ten trials, 22.1 sec. 



(f) Blind rats with vibrissae — (5 females) : 



Average number of trials in learning, 188. 

 Average time of the last ten trials, 45.8 sec. 



(g) Rats with the infra-orbital branch of the fifth nerve 



cut — (6 females) : 

 Number of trials, 441. 



Average number of errors per trial at close, 1.7. 

 Average time of the last ten trials, 11.3 sec. 



H. Report of Special Behavior of Animals of the Second Series 



(a) Rats with infra-orbital branch of the fifth nerve cut. — 

 The mode of cutting this nerve and the tests of sensitivity 

 which extended over a period of seven months have been, fully 

 described in another section of this paper. The noses and 

 vibrissae were entirely insensitive so far as we could see when 

 this experiment began, six weeks after the operation. These 

 animals had been used on the maze experimentation and were 

 in a sense trained animals as were all the other animals used 

 in the box. Some actual excerpts from the daily notes may 

 serve as well as anything else to indicate the behavior. 



June 1 1 . The behavior of these rats is very like that of those 

 used before, etc. 



June 15. These rats are not so active as some of the others. 

 They "nose" all about the box, however. They use their feet 

 on the upper edge of the partition and may get some cue in 

 this way. They made the association with the plate the first 

 time. 



June 26. Rat " i " went as rapidly as possible from C to A 

 to B and to the very end of each runway without any "nosing." 

 Rats " 4 " and " 5 " after a few trials and failures, sat for a quarter 

 of an hour at a time without moving. Every 15 minutes they 

 were lifted from the entrance where they lingered, given a sniff 

 of food and put back in the box. There was then a brief activity 

 and then quiet again. This conduct continued for three hours 

 when they finally entered the food box. 



