162 



THE ZOOLOGIST, 



either to a pan of fresh water or to a vivarium. This piece of 

 apparatus, though inexpensive, probably cannot be considered 

 so effective as the employment of a battery, whereby the animals 

 experimented on in a dry labyrinth are given a slight shock 

 every time they take a wrong turn, the motive employed being 

 the desire (only in the spring) to return to the water. 



I. 



Fig. 1 gives the ground plan of the first labyrinth used. It 

 was made of wood, with the sides of each trough a, b, c 3| in. 

 high and sloping in, so as to prevent the Newts from climbing 





..■■ ro 



Fig. 1. — a = entrance, Trough A. Trough c slopes up from salt solution. 

 I, r = left and right apertures into fresh water. 



up the sides. Each animal was placed facing forwards at the 

 beginning of the trough a. Palmates were employed in all the 

 experiments except where it is specially stated to the contrary. 

 An interval of at least ten minutes was given between each trial 

 up to the end of trial 15, after which the interval was reduced 

 to five minutes. 



Table 4* (p. 170) shows that the first Newt reduced the 



* The times were reckoned from the moment the Newt began to move 

 in the entrance until its nose reached the top of the slope at the exit. 



