SPIDERS AND INSECTS OTHER THAN ANTS 383 



communicated with this moist stone by means of a long stick 

 of wood. Thousands of individuals from the nest frequented 

 this stone. The noise of thunder or of the blasting of rocks 

 would send the insects hurrying to the nest. Even the clapping 

 of hands, which was probably too slight to jar the stone, would 

 produce the same effect; but the blowing of horns at various 

 pitches produced no effect. Andrews does not claim that this 

 is a case of audition ; he simply holds that the termites seem to 

 respond to certain concussions of the air. 



2. Sense of Smell. Andrews (9) thinks that many of the 

 activities of termites are influenced by stimuli which produce 

 something akin to the sense of smell. (See Andrews under 

 "Homing"). 



3. Vision. During the year two experimenters, Allard (8) 

 and Turner (57) have conducted experiments on the color vision 

 of insects. The methods and the materials used were different, 

 vet each investigator is convinced that the bees possess true 

 color vision. 



Allard (8) worked with various bees {Melissodes bimaculata, 

 Bombus, Entecnia, Apus). He used the following objects as 

 stimuli: normal cotton blossoms, and blossoms whose petals 

 had been removed; cotton blossom petals pinned to the stem, 

 a single petal thus pinned on, cloth petals arranged to resemble 

 a cotton blossom, cloth petals so arranged and covered with 

 real cotton petals, and, finally, cotton leaves wrapped around 

 petals to imitate a cotton bud. These objects were arranged 

 in groups of threes on a cotton field, the grouping being either 

 in a triangle or in a straight line. The results of Allard's ex- 

 periments lead him to the following conclusions : bees are guided 

 to cotton blossoms by sight, after they have entered the cotton 

 field; the inspecting process, however, is not dependent for its 

 initiation on the size and general appearance of the blossoms; 

 if a blossom is visible only to bees directly above it, it is seldom 

 visited; artificial objects are rarely inspected, probably because 

 the bees observe their differences in color and texture from the 

 natural objects; a blossom is inspected much oftener than it is 

 entered ; it is hard to determine the relative importance of sight 

 and smell in determining close inspection of a blossom, although 

 sight is instrumental in bringing about the first approach; bees 

 are much influenced by conspicuousness and coloration in per- 



