FUNCTION OF VIBRISSAE IN BEHAVIOR OF WHITE RAT 31 



it anastomoses with the seventh so that presumably the tactile 

 hair could mediate no sensation. The tip of the nose was made 

 insensitive as well. For description of the operation and tests 

 of sensitivity see appendix. 



The behavior of these rats showed in an exaggerated form all 

 that has been mentioned in connection with the rats whose 

 vibrissae had been removed. One feature which did not appear 

 in any of the others was a squealing at the end of blind alleys, 

 or when a slip was made. They did not use their noses so much 

 but seemed to depend more upon their feet. Perhaps an actual 

 record of some of the notes will show better than any other way 

 the nature of the behavior. Reference to the plan of the maze 

 will show the course to which the letters refer. (See fig. 7.) 



May 25, Rat i, ist trial. — Starts off cautiously; stays between 

 A and B 10 sec; falls; head over the side as if looking at the 

 floor ; on to B ; makes much use of feet ; toes are curling over 

 edge ; squeals ; washes ; on to E ; head over edge ; on to G walking 

 edges ; on to I ; the body is elongated and flattened ; washes ; 

 head over edge; falls; on G, H, G, H, N, O, N, O, on to end. 

 47 min. 



Rat 2, May 25, ist trial. — A to B walking edges; back to A; 

 washes; on to B, head over, still walking sides; head in E; back 

 to B; on to F; back to B; on to F. (This rat has a new way 

 of going, he walks with his hind feet on the path and his fore 

 feet feeling the edge in front of him.) D, slips; C; D; F; 

 falls; D; G; still walking close to edges; turns around two or 

 three times ; back to B ; on to F ; E ; F ; B ; G ; C ; G ; R ; bad 

 slip; on to end. 24 min. 30 sec. 



Here are some bits taken at random from the records of dif- 

 ferent rats and at different trials: Walks close to edge all the 

 way ; nose against floor ; sniffs as if smelling ; walks edges ; body 

 much flattened and lengthened; sniffing; slips; squeals as if 

 afraid of falling when she gets to the end of an alley; running 

 now ; nose down ; jumps from A to S ; put back ; when resting 

 these rats hang on by their toes; if touched they squeal; they 

 give every sign of seeing and smelling; up on hind feet sniffing; 

 halts at almost every turn with head over edge ; a cautious run ; 

 tries hard to get from A to S; tries to jump at K; up on hind 

 legs time and again : staggers as if dizzy ; carefully walking edges, 

 etc. (See fig. 17, Plate III.) 



