90 NORMAL AND EXPERIMENTAL POLLINATION. 



small distance is shown in the Monarda calendars, which were made in 

 areas but 3 meters apart. The flower group was essentially similar in both, 

 but one calendar gave 1,061 visits to normal Monarda, 131 to the mutilated, 

 and 66 to other species, while the other made simultaneously yielded 94 

 normal visits, 7 mutilated, and 55 to competing flowers. Essentially 

 similar results were obtained the next day, the first area giving 923, 208, 

 and 57 visits respectively, and the second 232, 76, and 237. It is thus 

 evident that a single record or calendar can not give an accurate or com- 

 prehensive picture of the numerical relations between a group of flowers 

 and insects. It is evident also that similar variations must be more or 

 less universal, and that they often explain the discrepancies between the 

 results of different investigators. 



Changes of position. — In general, the problem of alighting and securing 

 nectar from flowers in inverted, horizontal, vertical, or other changed 

 positions was solved with more or less readiness by the various bees. The 

 general behavior is well illustrated by the response to such changes in 

 Aconitum. Bombus juxtus and B. bifarius readily entered flowers with the 

 hood pointed downward, though this involved using the side petals instead 

 of the lower sepals as a landing platform. When the hood was turned to 

 the side, B. juxtus first hovered over such flowers for a moment before landing 

 successfully; in one case it slipped off, but tried again and succeeded. In 

 the case of inverted flowers, some individuals passed over them, others 

 hovered, and still others attempted to light and then flew away as 

 though disturbed by the change. Some landed at the lower sepals, turned 

 around, and entered upside down; at other inverted flowers they behaved 

 in exactly the same way, apparently recognizing the changed position before 

 landing. One individual landed three times at a group of inverted blossoms, 

 tried to reach the nectary without turning upside down, and failed in every 

 case. One B. bifarius mastered the problem readily and went to five 

 inverted flowers in succession, turning upside down just after alighting. 



A scrutiny of the behavior of various species of bees when confronted 

 by changes in the position of flowers makes it certain that they usually 

 recognize such changes at once. Since these are essentially changes in 

 form, they demonstrate that such insects at least do distinguish forms. 

 Differences in specific behavior are shown by table 50, in which Apis paid 

 relatively almost twice as many visits to inverted as to normal flowers, 

 Pseudomasaris about half as many, and Bombus went about equally to the 

 two. Differences in individual behavior are exemplified by the instances 

 given above for Bombus and they are revealed as well by practically all 

 studies with changes of position. They permit no doubt of the remarkable 

 intelligence of bees in problems that arise in situations with which they are 

 familiar. It seems obvious also that many of the individual variations in 

 response are not the result of differences in intelligence, but rather in what 

 is called temperament in man. 



Masking with cotton. — When the center of the flower was masked with 

 cotton, or cotton plugs put over or in the nectaiies, the bees were usually 

 unsuccessful in reaching the nectar or pollen. Most of them landed and 

 probed where the nectary or stamens should be, but were unable to reach 



