PHYSIOLOGY OF THE BEE. 89 



at all distances. Reaumur thinks they may, with their 

 hemispherical lens, act as microscopes. This point 

 needs further investigation, as the subject of the uses 

 of these two kinds of visual apparatus is, at present, 

 very far from satisfactorily elucidated. One remark- 

 able fact relating to the " stemmata " must be 

 mentioned. It is that, if they be covered with a 

 little opaque paint, the bee, on being let go, will fly 

 continually upwards. Dr. W. B. Carpenter considers 

 this curious fact due to automatic movements initiated 

 by the ganglia connected with flight, uncontrolled 

 by the visual impressions which the simple eyes 

 convey in their natural condition. Neither kind of 

 eye has a lid, but both are protected from dust by 

 numerous small hairs growing round them, and in 

 the points of junction of the facets. 



How far the eyes of bees enable them to distinguish 

 colours is still a moot point. On a priori grounds 

 we should expect that one very definite object in the 

 hues of flowers is to attract the notice of insects, 

 just as we have strong reason to believe that odours 

 exhaled in the vegetable world serve this purpose. 

 Sir John Lubbock has detailed a series of experi- 

 ments on this point, the following summary of which 

 is abstracted from his work on Ants, Bees, and Wasps. 

 He says, p. 304 : " In recording the results I marked 

 down successively the order in which the bee went 

 to the different-coloured glasses (on which honey 

 was placed). For instance, in the first journey from 

 the nest, as recorded below, the bee lit first on the 

 blue, which accordingly I marked I ; when the blue 

 was removed, she flew about a little, and then lit on 

 the white ; when the white was removed she settled 



