154 WASPS [CH. V 



Others have recorded that the removal of stones, 

 leaves and other small objects from the immediate 

 neighbourhood of the nests of some Hymenoptera has 

 'caused apparent confusion and perplexity to the returning 

 insect 1 . 



It is well known that the sense of smell is developed 

 to a remarkable degree in some insects, nor is it im- 

 probable that more senses than one are concerned in the 

 perfection of the "homing" faculty. There is, however, 

 much need of further accurate observation and experi- 

 ment on these and other animals with like powers. 



Food. The food of wasps is of a very varied nature. 

 Ripe fruit, sugary solutions and compounds are familiar to 

 all as their favourite articles of diet. They are also skilful 

 in securing the nectar from many flowers. I find "queens" 

 in early summer freely visiting the flowers of the white 

 Centaur ea and procuring the nectar in the legitimate 

 manner: later in the year I have known the workers 

 artfully to bite holes at the base of the spur of Pentstemon 

 blossoms and steal the nectar without entering the path 

 by which the flower would secure fertilisation. Other 

 observers have recorded blossoms of Fuchsia and of 

 Gladiolus as being damaged, and various Umbelliferous, 

 Labiate and Scrophularine flowers as being visited by 

 wasps. The gummy substance that is found on the buds 

 and leaves of some plants is also collected and apparently 

 used as a cement in the construction of the nest 2 . 



1 Of. G. W. and E. G. Peckham, Wisconsin Geol. and Nat. Hist. 

 Surv. Bull. 2, Sec. Ser. i. ; Fabre, Insect Life (Trans. D. Sharp). 



2 Janet, Mem. Soc. Zool. de France, vin. 1895. 



