398 INTRODUCTION TO ZOOLOGY CHAP. 



in a way unlike that of any of the social wasps or bees, for after 

 having laid an egg in the little burrow or tunnel that she has 

 excavated or taken possession of, each mother wasp collects and 

 places in the burrow one, or often several caterpillars which appear 

 partly stupefied, possibly, it is thought, owing to their having 

 been stung before they are stored away, though this does not 

 seem an established fact. On these caterpillars the larvae feed. 



Families 4 and 5. Digging Wasps (Pompilidae and Sphegidae). 

 The Digging Wasps differ from the Solitary True Wasps 

 (Eumenidae) in certain points of structure, though in habits, 

 and sometimes in coloration, they resemble them. They are 

 therefore classified apart from all the true wasps in the 

 division Fossores, of which Pompilidae and Sphegidae are the 

 two chief families. In these forms, the front wings are not 

 folded over longitudinally when at rest, and the eyes have 

 not the kidney shape characteristic of true wasps. They 

 all have the habit of burying with their eggs a mass of 

 stupefied insects to serve as food for their larvae. 



To this division belongs the red and black bodied, common 

 Pompilus maticus that stores up spiders 

 for its young ; also the Common Sand 

 Wasp (Ammophila sabulosa) which buries 

 caterpillars in the same way for food. 

 The Common Yellow Sand Wasp 

 (Mellinus arvensis) has a much shorter 

 Petiole, and it buries flies. There is 

 (Ammophila sabulosa). a weevil-killing Sand Wasp (Cerceris 

 arenaria), and also many British 

 species of Crdbro which usually form their burrows in the 

 pith of stems in rotten wood, or in the ground, storing them 

 with flies. Crdbro is black-bodied or wasp-like in colouring, 

 and its larvae spin tough brown cocoons. 



Classification of Bees and Wasps mentioned in Chapters 



XXIV. and XXV. 



Sub-order. HYMENOPTERA ACULEATA (the Stinging Hymenoptera). 



Division 1. Anthophila ( = Family 1. Apidae). Bees with 



protrusible proboscis, always feeding on nectar or 



pollen ; the body hairy, some of the hairs always 



being plumose or feathery. 



(For further classification see p. 386.) 



