34 



THE GUIDE TO NATURE 



sure that it was in perfect condition 

 and quite proper to serve as food for 

 her offspring-, she entered the remain- 

 ing' empty cell. To store these spiders 

 to her satisfaction, required quite some 

 time, but when once they had been 

 suitably placed, our industrious insect 

 lost no time in hurrying away to gather 

 in more victims. This manoeuvre was 



**■ -:££:■«>.. i"*-** 



THE MUD-DAUBER'S NEST SHOWING THE 

 EMPTY CELL WITH THE ENTRANCE SEALED. 



repeated on an average of every seven 

 minutes, but upon her tenth return to 

 the nest, she carried a small pellet of 

 mud instead of the usual spiders. This 

 was carefully placed upon the open end 

 of the cell and after flattening it some- 

 what with her head and fore feet, flew 

 off for more. 



At this point I intervened in behalf 

 of my experiment, and as a conse- 

 quence thereof, the sealed portion of 

 the entrance and the spiders were en- 

 tirely removed from the cell. Within 

 a very few minutes the wasp returned, 

 bearing its second load of material, and 

 this, as upon her previous visit, she 

 •cemented to the opening of the cell. 

 Now the wasp thrust her head through 

 the half closed entrance and after ap- 

 parently inspecting the empty interior, 

 again flew away, as I believed at the 

 time, in search of a new supply of 

 spiders to replace those which had 

 been removed. But this was not the 

 case, as we shall presently see. I now 

 left the immediate localitv of the nest 



fearing that perhaps my continual 

 presence would alarm the subject of 

 my experiment. In an hour I returned 

 only to find that the wasp had ignored 

 the fact that the cell had been emptied, 

 and had completely resealed it without 

 replacing the spiders or her egg ! 



In this case the insect clearly dem- 

 onstrated her inability to perceive, even 

 such a radical alteration as had taken 

 place in the cell during her absence. 

 She had simply proceeded to accom- 

 plish a certain, regular course of inborn 

 events, and owing to the fact that it 

 did not occur to her to alter any one of 

 these, even under the circumstances 

 which had been caused, it is plain that 

 there existed no mental activity, but 

 simply innat; muscular actions of a 

 reflective or unconscious nature. But 

 now let us turn to the subject of my 

 last experiment, which, it will be re- 

 membered, was the closely related, pa- 

 per-making cousin of the mud-dauber 



As I have stated before, the paper 

 wasps do not seal up their cells, nor 

 do they even store them with nourish- 

 ing food for the young. Owing to this 

 state of affairs, it would, of course, be 

 impossible to effect a similar alteration 

 upon their nest as upon that of the 

 mud-dauber. But the purpose of my 

 experiments was not simply to place 

 the two species in identical circum- 

 stances, but to discover, if when placed 

 under extraordinary conditions, either 

 would display in their actions, any evi- 

 dences of mental activity; or in fact, 

 anything which might give us better 

 reason for believing that insects are 

 sometimes governed by a power above 

 mere instinct. 



At the time of this experiment, the 

 paper wasps were adding several new 

 cells to the nest, which had grown too 

 small for the rapidly increasing colony. 

 These new cells were nearly finished ; 

 all but one, and of this perhaps a third 

 had been constructed by the tireless 

 insects. As I reached the nest, a wasp 

 was seen working upon the unfinished 

 cell, but she soon flew away in search 

 of a new supply of pulp. When she 

 had gone far enough to insure my feel- 

 ings against that unpleasant sensation 

 caused by her sting, the other members 



