REACTIONS OF THE MASON WASP, TRYPOXYLON 

 ALBOTARSUS, TO LIGHT 



C. H. TURNER 



Sumner High School, St. Louts, Mo. 



Several organ-pipe shaped cells of this species of mason wasp 

 were placed in an insect cage 1 6 inches high, 1 2 inches wide and 

 12 inches deep. The bottom and the framework of this cage 

 were constructed of wood, the sides and top were covered with 

 fine wire gauze. When not under observation, the cage con- 

 taining the insects was kept in a room with an average tem- 

 perature of 70 degrees, and in which the temperature never 

 fell below 60 degrees. The groups of cells ! were placed close 

 together on the floor of the cage. For food a watch-glass of 

 honey was placed in the cage. To supply the wasps with water, 

 under normal conditions, a cloth syphon led from a bent -neck 

 bottle of water to a Minot watch-glass of mud. 



DESCRIPTION OF EXPERIMENTS 

 SERIES I 



In this series of experiments direct sunlight was used as a 

 stimulus. The cage containing the wasps was placed in an 

 east window in such a position that all parts of the cage not 

 shaded by the framework were bathed in the direct rays of 

 the sun. The shadows ranged from two to two and a half inches 

 in width. 



While in the sunlight the wasps, as a rule, were quite active, 

 but the behavior was varied.. Many climbed the sides of the 

 enclosure; a few flew, at random, about the cage or hovered 

 before one of the sides; occasionally one would sip the honey 

 or drink the water. When wasps in walking upwards through 

 the sunlight arrived at the shadow produced by the upper 

 border of that side of the cage they would usually pass on into 

 the shadow; occasionally one would turn half around and move 

 along the line that separated the lighted from the shaded por- 



1 For the majority of these nests I must thank my friend Mr. Phil Rau of this 

 city. 



353 



