By dividing into three topics, we consider the phenomenon in which a Japanese honeybee is attracted to the KINRYOUHEN orchid.

1. Foraging behavior of a worker bee

Many flowers give off odors which honeybees like, and simultaneously they secrete sweet nectar. Honeybees are attracted to the flowers. A honeybee memorizes the scent and figure of the flowers, and visits the flowers. Moreover, since the place where a flower blooms is taught to other bees through the mechanism of the famous honeybee dance, many bees will visit flowers. Such behavior is called foraging of a honeybee, and flowers are pollinated by the honeybee. Many flowers which have been pollinated by a honeybee, attract honeybees in this way. However, there is the nectary of the KINRYOUHEN, outside the flower and a nectary located on the side of a flower. The nectary attracts an ant. Still, a honeybee visits KINRYOUHEN and inserts its' body in the flower. There must be a good smell for the bee, the same as that with other flowers. However, a person cannot detect its' smell. Pollen becomes attached to the back of the bee, and it returns to the nest.
I investigated whether there would be any orchid foraging of Japanese honeybees in addition to the KINRYOUHEN orchid. The next table shows the results. The honeybee forages for KANRAN , SHUNRAN, SHIRAN, SURUGARAN, and KAMPOURAN. A worker bee visits a flower of these orchids. However, a swarm is not attracted to these orchids like it is to the KINRYOUHEN.

Japanese name	Science name	Result
KANRAN	Cymbidium Kanran	+
SYUNRAN	Cymbidium virescens	+
SOSINRAN	Cymbidium Gyokuchin var.Soshin	-
SURUGARAN	Cymbidium ensifolium	+
HOUSAIRAN	Cymbidium sinense	-
KANPOURAN	Cymbidium dayanum	+
SETTUKOKU	Dendrobium monile	-
FURAN	Neofinetia falcata	-
TOKISOU	Pogonia japonica	-
SIRAN	Bletilla striata	+
EBINE	Calanthe discolor	-
NAGORAN	Aerides Japonicum	-

KANRAN	SYUNRAN
SYUNRAN	SURUGARAN

2. It is a strange phenomenon that a drone forages the KINRYOUHEN

Originally a drone does not collect pollen or does it collect honey. A drone flies away from his nest in order to copulate with a queen. A drone flies about the place (above the crown of big tree) where copulation is performed, and returns to the nest. Because a drone does no other things, we call the drone an idler in English.
This drone is attracted to the KINRYOUHEN, and a drone inserts his head into the flower. Then, pollen will be attached to the back of the drone and the drone will carry out pollination as a result. However, the behavior of a drone which flew to the flower of the KINRYOUHEN, differs a little from a worker bee's behavior. The table below shows the results of observations of worker and drone bees when they come to the flower of the KINRYOUHEN which has been set near the nest.
While a worker bee returns from a flower soon, a drone is on the flower for a long time before returning to the nest. Consequently, a drone uses up all of the energy in his body and falls on the ground. Probably, something must come from the flower in order to attract such a drone.
A drone gathers near the queen by attraction to the pheromone for copulation, which a queen sends out. At the time of a swarm, many bees come from the nest and make the bee ball of the swarm. Drones are also contained in the bee ball of the swarm. The bee ball of the swarm is formed by the aggregate pheromone which the workers send out. Therefore, a drone will also be attracted to this pheromone. In order to attract a drone to a flower, the flower of the KINRYOUHEN must send out the same pheromone which the queen sends out, or the aggregation pheromone which worker bees send out.

Observation of the Japanese honeybee which visits the KINRYOUHEN
(1997. 5/4/1997. fine-weather, maximum temperature is 25℃)
●A bee with pollen○The bee which visited the flower↓Time which the bee stopped at the flower

Time	Worker	Drone
10:35
10:50
11:05
11:20	●●●●●●●●●●
11:35	●	●
11:50
12:05	●	○
12:20
12:35	●●●
12:50	●●
13:05	●	○ ↓
13:20		● ↓
13:35		●○○○ ↓↓↓↓
13:50	●●●●●●●	●○○○ 　↓
14:05	●●●●●	○
14:20	●●●●●●●●
14:35	●●●●●●	○○ 　↓
14:50	●●●	○
15:05
15:20	●
15:35

3. Swarm and absconding colony of Japanese honeybee is attracted to the KINRYOUHEN orchid

If the blooming KINRYOUHEN is placed near the colony when the bees are swarming, in many cases, a colony will be attracted to the KINRYOUHEN. However, it does not necessarily attract. Alternatively, it may be attracted to a thick branch of a tree or a board where swarms have previously been-attracted. When observed, it seems that bees which have begun to flock, have said "we will concentrate here" to the rest of the flying bees. A bee that has landed raises its abdomen and emits a pheromone. If many bees flock, many pheromones will be released and finally all bees will flock to one place. When bees are attracted to the KINRYOUHEN, the smell of the KINRYOUHEN is more attractive than the smell of a group of bees.

Experiment

Does the KINRYOUHEN orchid give off the same substance as the pheromone of an aggregation of bees? This is not yet well understood. The next experiment was tried in order to solve this problem.

1.I did not wait for a bee to flock to the KINRYOUHEN, but when I tested the KINRYOUHEN, I discovered a method in which the bees will surely flock to the KINRYOUHEN. It is the following method. A sheet of plywood of 90x90cm was prepared for the yard. The KINRYOUHEN in which the flower is in bloom, was set at the upper end of the plywood in a flowerpot, and bees on a comb were dropped on the plywood (200 to 300 bees). The result is as shown in the photograph. The bees walked and flocked to the KINRYOUHEN orchid.

The bees attracted to KINRYOUHEN	The bees attracted to KINRYOUHEN (yellow flower)

2.The flower of the KINRYOUHEN consists of a column, a lip, petals, and sepals. What attracts the Japanese honeybee to these portions? I separated the flower into each portion, and I set each portion near the bees, and observed the attraction of the bees. The result was completely unexpected. The bees were not at all attracted to the columns and lips, which form the central part of a flower, but instead were attracted to the petals and sepals. (Enlargement). Through this experiment, I understand the nature of the substance which has come out of a petal or sepal, but it still is not clear what this substance is.

Bees attracted to sepals - petals	Bees attracted to sepals and petals

I tried the same experiment using the SHIRAN orchid on which foraging behavior of the bee had been observed. The petals and the sepals of the SHIRAN do not attract the bee like that of the KINRYOUHEN orchid. From this fact, the substance which attracts the group bees, differs from the substance which elicits foraging behavior of a bee. The former is emitted from SHIRAN but the latter is not emitted from SHIRAN. It is thought that the KINRYOUHEN emits both.

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