the homing of the burrowing-bees. 249 



Experiment 2. 

 The same conditions as in experiment one. 



At 10:20 A. M., the bee arrived from its trip, hovered for less 

 than half a minute and then dropped into the nest. At 10:24 

 A. M., the bee departed, without stopping to explore the sur- 

 roundings of the nest. 



Experiment 3. 



About fan y incites to the east of the nest opening, a hole loas made 

 in the ground. Over this hole was placed the piece of zvhite paper, 

 ivith the hole in the center, zvhich was adjusted over the nest in ex- 

 periment two. A piece of water-melon rind, xvith a thirteen mm. 

 hole in the center, zvas so adjusted over the nest as to have the hole 

 in the rind coincide ivith tJie opening of the burrow. One half of 

 the rind zvas brozvn, the other half yelloivisJi green ; the line divid- 

 ing these tivo colors bisected the hole in the center of the rind. 



At 10:47 A. M., the bee arrived with its burden of pollen. It 

 hovered above the melon-rind for a moment, then circled about 

 the place. At 10:48 A. M., after a search of one minute, the 

 bee entered the nest. On leaving the nest at 10:59 ^- M., the 

 bee examined carefully the surroundings before departing. 



Experiment 4. 

 While the bee zvas afield, the piece of zvater-mclon rind zvas re- 

 moved and a rectangular piece of white paper, eight cm. long and 

 five cm. wide, zvas arched over the nest in such a zvay as to form a 

 tent six cm. high, the east and zvest ends of zvhich zvere open. The 

 rectangular piece of zvhite paper, with the hole in the center, zvhich 

 was left in the same position as in experiment three, zvas situated 

 just in front of the eastern opening of the tent. 



When the bee arrived, at 11:15 A. M., it circled about for two 

 minutes [until 11:17 A. M.] and then dropped into the hole 

 over which the rectangular piece of paper, with the hole in its 

 center, had been adjusted. It emerged at once and, after circling 

 about for a short time, reentered the same hole. It emerged 

 immediately. Finally, at Ii:i8 A. M., three minutes after ar- 

 riving on the spot, the bee entered the tent, through the eastern 

 opening, and dropped into the burrow. On emerging from the 

 nest, at 11:31 A. M., the bee hovered a moment inside of the 



