A brief review of the literature on this subject is given. By means of "training table" experiments in which use was made of the Latin square system in order to allow of rapid statistical analysis of the results obtained, it was shown that:
(1) The honeybee prefers dilute sodium chloride and ammonium chloride solutions to distilled water.
(2) It does not prefer concentrations of these salts higher than N/20 solutions and solutions of various other salts to distilled water.
(3) The honeybee appears unable to distinguish between N/160 sodium chloride or N/160 ammonium chloride and distilled water.
(4) The honeybee is probably largely attracted to such sources of drinking water as rain water from gutters choked with decaying organic matter, sewage effluent, etc.: by a water perception sense coupled with an olfactory appreciation of various volatile substances contained in these sources of water.
(5) The volatile substances present in the distillates from the various naturally occuring solutions examined could be absorbed on to animal charcoal to a large extent, in which case the resulting supernatant fluid was found to have lost its great attraction for the honeybee and was no longer clearly distinguished from distilled water.
(6) The salts contained in these sources of drinking water do not appear to play an important part in attracting the bee thither.
(7) It was found possible to express the preference shown by the honeybee for various solutions by means of numerical factors based on distilled water having an arbitrary factor of 10. Forty different solutions have been arranged in order of preference by this means.