224 PRINCIPLES AND CONCLUSIONS. 



"While the wasp was still searching for the nest, the top shade of window number four 

 was lowered and the corresponding shade of window number three raised as far as possible. 

 This reproduced the conditions under which the wasp had originally worked. Almost 

 immediately the wasp found the nest! 



"From these experiments it is evident that in finding its way back to its nest, the mud- 

 dauber is guided neither by what is known as a homing instinct nor by what Pieron has 

 called a kinesthetic reflex; for if either assumption were true, a manipulation of the light 

 should not have altered the wasp's behavior. Evidently light plays a prominent role in 

 the homing of wasps, yet the behavior of the mud-dauber is not a phototropism, for in no 

 case did the wasp so orient itself as to have the major axis of its body parallel to the rays 

 of light. Neither is the wasp's behavior merely a reflex response either to brightness or 

 to the direction of the rays of light; for if that were the case, in experiment six, when all 

 the shades of windows number two to four were lowered except the top shade of window 

 number two, the wasp should have flown, not to the wall to the west of window number 

 three, but to window number two. But brightness is not the only factor which influences 

 the movements of this wasp; else, when all the shades of windows number two to six 

 were lowered, it would have been impossible for it to rediscover the nest. This series of 

 experiments warrants the induction that, in the wasp's memory, the nest is located in a 

 certain direction and at about a definite distance from a bright patch which is situated 

 at a known elevation in a peculiar environment. 



" The above statement predicates to wasps memory and an awareness of space relations. 

 As to the existence of memory, these experiments furnish unequivocal evidence, and they 

 warrant the conclusion that the flying mud-dauber, like the creeping ant, is guided by 

 certain landmarks, and that light plays a prominent role in furnishing such landmarks." 



Experiments on the orientation of bees in homing. — Frisch (1914: 86) 

 has summarized the results of others as to the practical value of painting 

 hives in color and has contributed the details of some of his own experiments 

 in this field. All of these support the conclusion that honey-bees, when 

 their hive is set apart from the neighboring ones by means of color in a 

 striking manner, utilize this as the chief means of orientation in finding 

 their home. They further show that bees observe not only the color of 

 their own hive, but also the color and relative position of neighboring ones. 

 In consequence the bee-keeper can hardly devise a better and more certain 

 way of enabling bees to locate their own hive than that of painting it in 

 colors. For this, however, it is desirable to paint the entire outside and 

 not merely the landing-board or the entrance. Care should be taken not 

 to employ for neighboring hives colors that are distinct for our eyes but not 

 for those of the bee, such as blue and purple, or black and scarlet-red. As 

 a result, when hives are numerous, it is better to use color combinations for 

 each, such as one-half red and the other yellow, rather than too many 

 colors or shades which may merely be distinct to us. 



Homing ability in Polistes. — The Raus (1918:273) have made a 

 number of experiments on the homing ability of the wasp, Polistes pallipes, 

 which they summarize as follows: 



"Out of 33 queens which were taken for various distances from one-eighth mile 

 to 2.7 miles, 24 returned to the nest. Of the 22 taken out for the first time, 17 reached 

 home; of the 11 which had made previous test flights, 7 successfully returned. With 

 the workers, the results were quite different. Of 112 workers that were used, only 

 28 returned, and those that returned did so only in the short flights. The long dis- 

 tance tests always gave negative results. Out of the 17 new workers that were ex- 

 perimented upon, none returned; of the 33 old workers, 14 came back; of the 62 

 workers of unknown age, 14 returned. According to the law of chance, it is easily 

 possible that these 14 out of the 62 workers of unknown age may have been old ones. 



