INTRODUCTION. 15 



end of the body, which may be withdrawn into the body or be 

 permanently protruded. 



Hymenoptera are a very large class, including as they do, many 

 insects of such widely different habits. They are popularly known 

 as wasp-waisted flies, such being an easily recognised characteristic. 

 The Ants, Bees, Wasps, Ichneumon, and Gall-flies, of which 

 we use some few, and the Saw-flies are included in this order. 

 The Hymenoptera are looked upon by entomologists as the most 

 interesting and intelligent species found in the insect world, con- 

 taining as they do the bulk of those which have communal existence 

 and live in colonies, where laws exist and the strictest discipline is 

 maintained. Many of the species are beautiful alike in form and 

 colour. Very few of them are aquatic insects, but many get on 

 the water accidentally. This is possibly one reason why at times 

 they are so attractive, as once on the water they buzz and make 

 a great fuss instead of quietly going ashore. If asked which is 

 our most beautiful fly, one would be puzzled to answer, but an 

 exceedingly handsome fly is the Ruby-tailed Wasp, or Fire-tail 

 {Chrysis ignita), plate 8, fig. 85, and there is a similar fly (C. rubii) 

 about half the size. One often wonders at fly tiers making " fancy " 

 flies, when there are in nature such magnificent examples to be copied. 

 These two flies are said to be enemies of the common solitary wasp, 

 preying on their larvae ; laying their own eggs in the comb of the 

 wasp ; their larvae eating the wasp grubs. 



Plate 8, figs. 78, 79, shew Nematus niger and Nematus lucidus, 

 two very common flies, the former much in evidence in the Spring 

 time, and the latter practically all the season. 



Early writers on fishing flies all give the Hawthorn Fly {Bibio 

 marci), plate 2, fig. 20, as one of importance, but we think Nematus 

 niger is much more widely distributed, and abundant at the water- 

 side ; we believe it is at times mistaken for and erroneously called 

 the Hawthorn Fly. 



Plate 8, fig. 84, the small Sand Wasp {Allantus arcuatus) is 

 always found when the Soldier Beetle is moving, and frequently 

 side by side on the same hemlock or other flower. 



