368 'Journal of Comparative Neurology ajid Psychology. 



bers and between the last chamber and the well were covered with 

 Turkish toweling one layer thick. 



With a fine camel's hair pencil, the upper surface of the abdomen 

 of any ant used for individual experiments was marked with water- 

 color paint. If more than one ant was used simultaneously for 

 such experiments, each was given a distinctive hue. In all experi- 

 ments with marked ants, any unmarked ant that visited the stage 

 was immediately imprisoned. 



The stage used consisted of a piece of white bristol board 15 

 cm. square; in the edges of two opposite sides perpendicular slits 

 were made 2 cm. from each corner, for the purpose of attaching 

 inclines to the stage. The center of this platform was attached, 

 by means of a pin, to the cork of a bottle about 12 cm. high. 

 Unless otherwise stated, a new stage was used for each series of 

 experiments. 



All the mclines were made ot the same bristol board as the stage 

 and were about 3 cm. wide and usually 30 cm. long. For special 

 purposes inclines were made by pasting two of these end to end. 

 They were also modified in other ways. When an incline led 

 from a stage downward, it was always attached so as to project 

 2 cm. above the stage except when a dark chamber was used. 

 When the incline led from the stage upward it was always attached 

 so as to project 2 cm. below the stage. The dark chamber con- 

 sisted of an inverted pasteboard box 8x4x1 cm. A flap about 

 one centimeter wide and attached above was cut out of one end, 

 and was pressed inwards to furnish a door through which the ants 

 could enter the dark chamber. In order to observe what was 

 happening on the under side of the stage and incline, a small mir- 

 ror, inclined at the proper angle, was placed on the island, at one 

 side of the stage. 



Unless otherwise stated, preparatory to each series of experi- 

 ments, the nest with its entrance open was placed on a Lubbock 

 island for one or two days in order to familiarize the ants with the 

 island. 



Historical Resume. — Students of ant behavior may be conven- 

 iently grouped into four schools: first, those who claim that ants 

 lead a purely reflex life; second, those who hold that ants lead a 

 purely instinctive life; third, those who grant that ants possess a 

 limited amount of intelligence; fourth, those who insist that ants 

 are endowed with anthropomorphic intelligence. 



