408 C. H. TURNER 



Turner (105) tested the ability of the common roach to learn 

 a maze similar to those used so much by students of vertebrate 

 behavior. The maze used was open, i.e., there were no walls 

 surrounding the runways. The maze contained several blind 

 alleys, some of which were complex. When in use, the maze 

 was supported by means of slender glass pillars above a wide 

 pan of water, so that if the roach fell off of the runways it was 

 sure to fall into water. The roach to be tested was always placed 

 on the same portion of the maze, and before each trial the run- 

 ways were washed with alcohol, to remove any odor that may 

 have been left there by a roach. When a roach was placed on 

 the maze for the first time, it always made many mistakes, such 

 as rushing into or falling into the water, going into blind alleys 

 and retracing its steps when on the right pathway. Gradually 

 these errors were eliminated and the roach took the shortest 

 path from the place where she was placed on the maze to its 

 cage, which was reached by a paper inclined plane. The inves- 

 tigator draws the following conclusions: (1) By arranging the 

 trials at intervals of half an hour, a roach may be taught, within 

 a day, to run the maze. (2) The gradual manner in which errors 

 are eliminated would cause one to conclude that the roach learns 

 to run the maze by the trial and error method; yet, in so doing, 

 it utilizes sense stimuli. This is evidenced by the careful manner 

 in which it examines (often over and over again) the corners 

 and the edges of the maze and the space adjacent thereto. (3) At 

 times the roach acts as though experiencing the emotion the 

 psychologists call will. (4) Although the effects of training per- 

 sist for a long time, yet the memory of the roach is poor; for, 

 after an interval of twelve hours, marked lapses are noticed. 

 (5) In its toilet activities the behavior of the roach resembles 

 very much the toilet-making activities of the cat. (6) In their 

 behavior on the maze roaches display marked individuality. 



TECHNIQUE 



Hentschell (57) discusses insect aquaria, and Zetek (126) 

 describes, in detail, how to raise mosquitoes in aquaria. 



Hunter (62) describes and illustrates an apparatus which will 

 maintain constant or variable temperatures from 60° F. to 

 -10° F. 



In his experiments on the flight of mosquitoes, Zetek (126) 



