OCT. 1906. OUK KNOWLEDGE OF THE VISUAL MEMORY OF BEES. 
137 
extent first the site, and then the appearance of the nest-entrance, 
for the purpose of noting the effect on the bee's behavior. 
The bee was visiting and leaving the nest as follows : 
entering at 10:48:13 a. m. 
leaving at 10 148 :50 A. m. 
entering at 10 :49 :io a. m. 
leaving at 10 :5i :20 a. m. 
Experiment i.— As soon as the bee had departed the stem was 
pushed upward, and in this manner the nest-entrance was placed 
3 inches above the former site and brought into somewhat differ- 
ent surroundings. 
At 10:52:10 the bee returned along the usual course leading 
to the former site of the nest-entrance. Not finding the latter 
immediately it started to fly around, and soon discovered the 
opening, but it made a careful survey of the stems and grasses 
around it before entering at 10:52:52, 42 seconds after its return. 
At 10:53 : 35 ^ l e; ft the nest, and returned again at 10:54:10 to 
the former site of the entrance. It did not go in until 10:54:20 
(10 seconds later), after having examined the surroundings as 
before. 
In its subsequent visits it 
returned at 10:56:58, entered at 10:57: 5 (7 seconds) ; 
returned at 10:57:58, entered at 10:58: o (2 seconds) ; . 
returned at 10:59:40, entered at 10:59:42 (2 seconds) ; 
always flying in too low before finding the entrance. 
At the next visit, at 11 :oo:45, it flew directly to the entrance 
without an error, and the same was the case with all of the follow- 
ing visits at 
11 :i :30, 
11 :2 :20, 
11:3 -40, 
11:5:18, 
11:7: 5. 
Experiment 2.— The bee had evidently become acquainted with 
the new order of things, and a blackberry leaf with a round hole 
in the middle was pushed over the end of the stem. The entrance 
to the nest was now situated in the middle of the vertical green 
leaf, and this arrangement had given to the immediate surround- 
ings of the nest opening quite a different aspect. 
