OMNIVOROUS MOLLUSCS, INSECTS, AND CRUSTACEANS 251 



interesting particulars are given by Sharp (in The Cambridge 

 Natural History) of the way in which the queen wasp feeds the 

 young larvae of the colony she has founded: " As the eggs 

 soon hatch, and produce larvae that grow rapidly, the labours of 

 the queen-wasp are chiefly directed to feeding the young. At 

 first she supplies them with saccharine matter, which she pro- 

 cures from flowers or fruits, but soon gives them a stronger diet 

 of insect-meat. This is procured by chasing living insects, and 

 the hornet is said to be very fond of the honey-bee, but, as a 

 rule, Diptera [i.e. two- winged flies] are the prey selected. When 

 an insect has been secured, the hard and innutritious parts are 

 bitten off, and the succulent parts, more especially the thorax, 

 which contains chiefly muscular tissue, are reduced to a pulp by 

 means of the mandibles; this is offered to the larvae, which are 

 said to stretch out their heads to the mother to receive the food, 

 after the manner of nestling birds." 



Examples of carnivorous and vegetarian ANTS have already 

 been given (pp. 103, 206), and it need only be added here that 

 many of the social kinds, including several British species, feed 

 on both animal and vegetable matter. As to the former, it is 

 interesting to note that ants, especially in tropical countries, play 

 the part of scavengers, and share with vultures the office of 

 devouring dead bodies. This propensity is sometimes utilized 

 in this country when a carefully-prepared skeleton of some small 

 animal is desired, for if the carcass be placed in the neighbour- 

 hood of an ants' nest it will soon be picked perfectly clean. On 

 the other hand, ordinary ants have a great love for sweet sub- 

 stances of all sorts, and cases are frequent where they raid houses, 

 and particularly confectioners' shops, in search of such things as 

 sugar, honey, jam, or articles into the composition of which these 

 enter. 



The TWO-WINGED FLIES or DIPTERA possess much-specialized 

 suctorial mouth -parts (see pp. 120, 121), commonly used for 

 obtaining either animal or vegetable food. Allusion has already 

 been made to the case of Gnats (pp. 120, 215) and the like, 

 where the female sucks blood, while the male is believed to live 

 on plant-juices, which may be put paradoxically in some such 

 statement as " the individual is limited to one kind of food, but 

 the species is omnivorous". The common House-Fly (Musca 

 domestica) (fig. 463), however, is truly omnivorous, and settles 



