8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 8l 



Lutz (46) in 1924 used colored filters as windows in a box and 

 determined that insects can readily distinguish ultraviolet rays. Certain 

 individuals, particularly Lepidoptera, stubbornly refused to respond 

 to any condition of illumination, even clear sunshine, when they were 

 placed in the box. Certain others responded only when urged to do so 

 by jarring the box, but then their reactions were definite. The skipper 

 Epargyreus titynis, when put in the box " went to sleep," but when 

 touched it went to the ultraviolet filter and tried to get out. 



Other recent workers, whose apparatus and procedure are recom- 

 mended to research students, have obtained results showing that insects 

 respond to the color of certain wave lengths. Thus Abbott ( i ) deter- 

 mined that a certain ant responds most readily to yellow, and Ber- 

 tholf (3) ascertained that red does not stimulate honeybees as much 

 as it does humans, but that violet stimulates them more. 



Besides consulting the references already cited students are advised 

 to consult others, particularly Parsons (71) and Luckiesh (45). 



One of the most recent papers on this subject is by Peterson and 

 Haeussler (74), who studied the responses of the oriental fruit moth 

 (Laspeyresia molesta Busck) and the codling moth {Carpocapsa 

 pomponella L.) in 1925, 1926, and 1927. Several thousand individuals 

 of each species were tested after dusk at Riverton, N. J., where 

 an abundance of material could be secured. Two types of apparatus 

 were used, but the most satisfactory one is what they call a " four- 

 way light apparatus." The colored screens and lights used were sub- 

 mitted to Dr. P. A. van der Muelen of Rutgers University, who 

 examined them spectroscopically. Their summary in part is as fol- 

 lows : Oriental fruit moths and codling moths seek the light side of 

 containers in which they are placed. This indicates that they are 

 photopositive under ordinary conditions. When tested under labora- 

 tory conditions in the four-way light apparatus, with the four compart- 

 ments equally lighted with white lights, practically the same number 

 of moths went into each compartment. When the compartments were 

 unequally lighted, the largest number of moths went to the strongest 

 light. When the moths were given the choice of lights varying in color 

 from red to violet and the ratios of relative intensities of the colored 

 lights were approximately equal, practically all of the motljs went 

 to blue and violet lights. Few or none were attracted to the red light. 

 Orange and yellow lights, when compared to bluish ones, were also 

 unattractive. Green light, possessing no blue rays, was likewise un- 

 attractive. Violet light was preferred to blue, and ultrapurple wave 

 lengths appeared to be more attractive than violet. Ultraviolet light 



