Solitary Bees and Wasps 



she flies away as far as her failing strength will carry her, 

 and dies. The young sand-wasps, however, will perpetuate 

 her work, for her eggs will furnish lusty grubs well pro- 

 vided with living food, seeing that their mother was careful 

 to paralyse and not to kill her prey, thereby ensuring that 

 it would be in fresh condition for her offspring. 



Two American entomologists noticed a very distinct 

 personality among the female sand-wasps they watched at 

 work. " This personality was not of individual appearance 

 but of such mental attributes as careful painstaking or 

 carelessness, and industry or laziness. One seemed to 

 hurry tremendously and spent no time on non-essentials. 

 Another was an artist, working for a long time on the 

 closing of her burrow, arranging the surface with 

 scrupulous care and sweeping away every possible particle 

 of dust to a distance. Still another went to the extreme 

 in carelessness, carrying the caterpillar in a very careless 

 way and making a nest which was a very poor affair. 

 Still a fourth was the most fastidious and perfect little 

 worker of the whole season, so nice was she in her adapta- 

 tion of means to ends, so busy and contented in her 

 labour of love, and so pretty in her pride of her completed 

 work. In fact, they seem to have almost as much in- 

 dividuality as human beings, and the result of these 

 observations has a strong bearing on the discussion of 

 instinct." Fabre, the ^French entomologist, who studied 

 the same insects, considered that they were inspired by 

 automatically perfect instincts which can never have 

 varied to any appreciable extent from the beginning of 

 time. Deviation from the regular rule, he thought, would 

 mean extinction. The American authorities, however, 

 found that variability was " the one unmistakable and ever- 

 present fact, and this variability existed in every particular : 

 in the shape of the nest and in the manner of digging it, 

 whether it is left closed or open, in the manner of stinging 

 the prey and of crushing it, in the manner of carrying the 

 victim, in the way of closing the nest and in the condition 



38 



