THE ZOOLOGI 



No. 902.— August 15th, 



HABIT-FORMATION IN A WASP (VESPA sp.). 



By J. M. Dewar, M.D. 



The ability of Arthropods to profit by experience is well 

 known. Much, however, remains to be discovered regarding the 

 mechanism and rate of learning. Towards the solution of 

 these problems the present paper is a contribution. Experi- 

 ments were made, in the month of June, on a queen Wasp* 

 which had her nest in a bank of boulder-clay. Entering the 

 exposed face of the clay through a hollow root, a long tunnel 

 led obliquely backwards and to the right, to end in the wall of a 

 disused rabbit-burrow. The paper nest was affixed to the end 

 of the tunnel, and projected freely into the airway of the 

 rabbit-burrow. The nest was distant about 40 cm. from the 

 plane of entrance to the burrow, and was visible to the human 

 eye at a distance of from three to five metres, according to 

 the intensity of the light. The entrances to the tunnel and the 

 rabbit-burrow were about 50 cm. apart. A nest from the same 

 locality, but well removed from the scene of the observations, 

 contained nothing but eggs and grubs ; .and such appeared also 

 to be the condition of the nest of the experiments, though it was 

 not opened up to make sure of its state. During the whole period 

 of the observations nothing occurred to raise a doubt as to the 

 identity of the Wasp visiting the nest. 



* Probably Vespa germanica, F. The identification rests solely on the 

 markings of the dorsum of the abdomen. 



Zool. 4th ser. vol. XX., August, 1916. z 



