INVERTEBRATE PHOTORECEPTORS GG7 



and no response to X rays, radium emanations, or 13 and 7 rays of various 

 hardnesses. Studies of the spectral responses and color vision of the 

 honeybee have leaned on conditioned responses and observations in rela- 

 tion to natural and artificial flowers. Kathariner (1903) used colored 

 feeding boxes; Lovell (1909, 1910, 1912) recorded the colors of flowers 

 visited by marked bees and doubted the constancy of the bee to any hue. 

 Turner's experiments (1910) with training bees, like those of Von Frisch 

 (1913 1923) and those of Ladd-Franklin (1913) and Hess (1909 1920), 

 are strictly antagonistic in approach and results. Von Frisch's findings 

 correspond, however, to those of Kuehn (1921-1927), Kuehn and Pohl 

 (1921), Kuehn and Fraenkel (1927), Baumgaertner (1928), and others 

 and fit well with Bertholf's spectral-sensitivity studies (1927, 1931). The 

 drone fly Eristalis appears similarly to be able to distinguish colors (Use, 

 1949; Kugler, 1950). 



Color response and spectral sensitivities of the honeybee have been 

 studied together by Opfinger (1931) and Sander (1933). As in experi- 

 mental work by Hess and others, these workers used colored and gray 

 papers as test areas. None of these papers was calibrated in the ultra- 

 violet region, which is so strongly stimulating to the honeybee, so that 

 conclusions drawn from these studies are of doubtful value. Lotmar 

 (1933) and Hertz (1937a, b,c) attempted to check on this aspect, but even 

 through measurements of ultraviolet reflectance from standard papers 

 (Hering's series) they were unable to validate the earlier work. That 

 the ultraviolet-sensitivity problem is important was emphasized by Stitz 

 and Beyer (1927), who found changes in life history in the hive (apart 

 from "harmful" effects) after installation of an ultraviolet source within 

 it. Even the color of paint on the outside of a hive has occasioned debate : 

 Some have argued in favor of contrasting hive colors to help bees find 

 their way home more easily, whereas others have pointed out that, when 

 bees swarm, they will either require a new^ hive of the same color (necessi- 

 tating a large stock of empties on hand) or distribute themselves into the 

 nearest hives of the same color. 



Another approach to spectral sensitivity and color vision has been 

 made through chromatophore changes observable particularly in mollusks 

 and arthropods (Parker et al., 1935). That in cephalopods is unique in 

 being directly under nervous control, whereas that in the crustaceans 

 appears regularly to be mediated by hormones in a neurochemical mecha- 

 nism of considerable complexity. Color changes in response to environ- 

 ment and seemingly to vision have been studied also among the crab 

 spiders (especially Misumena) since the first record by Angus in 1882. 



Insect coloration has been subject to philosophical comment, such as 

 is summed up by Poulton (1890) or more realistically by Judd (1899), 

 Hesse (1933), and Carrick (1936). Matching of environmental colors has 

 been studied at length in the walking-stick insect Dixippus {Caurasius) 



