56 GUIDE TO INSECTS. 



their biting habits, and the discovery of the part played by them in 

 conveying disease, with which the species of Anopheles are specially 

 connected. 



Tipulida. Daddy-long-legs, or Crane-flies. The larvae, which 

 are called Leather-jackets, live on roots, and sometimes do consider- 

 able mischief to lawn? and root crops. Some species live in decaying 

 wood and other vegetable matter. 



The Asilidce and Empidcz are predaceous. They live on other 

 insects which they capture, pierce with their rather short, strong 

 proboscis and suck dry. 



The Syrphidcv, or Hover-flies. The larvae of these flies are very 

 diverse in their habits. Some of them are beneficial, as they feed on 

 Aphids (Green-fly). They somewhat resemble leeches in form, and 

 may often be found among the Aphids on roses or on fruit trees, &c. 



The larvae of Eristalis and its allies are totally different. They 

 live in water saturated with decaying matter and filth. In order to 

 obtain air the larva is provided with a long tube-like tail, which is 

 capable of being extended for a considerable distance to reach the 

 surface of the water, whence these larvae have been called rat-tailed 

 maggots. The larvae of Volucella live in the nests of humble-bees 

 and wasps. Those of Merodon feed in narcissus bulbs, and some- 

 times cause serious loss. 



Tachinidte. The larvae of the majority of Tachinidce, live in 

 caterpillars. This they do without killing the caterpillar until they 

 are fully grown, when they pierce through the skin of the host, and 

 almost immediately assume the pupa form. 



CEstridce. This family is of small extent but of great importance, 

 since the larvae live at the expense of vertebrate animals. Gastrophilus 

 larvae, called " bots," find their way into the stomachs of horses. 

 The larvae of Hypoderma lineatum and H. lovis^ the Ox Warble 

 flies, are found under the skin on the backs of oxen, whilst those of 

 (Estrus oviSi the Sheep Bot, are developed in the nasal and frontal 

 sinuses of sheep. 



Another group of flies of considerable interest are the Hippo- 

 boscidcz, which live on mammals and birds. Hippobosca equina, 

 known as the Forest Fly, is found on horses ; Lipoptena cervi on 

 deer. Stenopteryx hirundinis attaches itself to the house-martin. 

 Melophagus ovinus, another member of this family, is known by the 

 misleading name of Sheep-tick. It is a curious wingless insect, 

 which lives among the wool of sheep, and when numerous has an 

 injurious effect on the fleece. 



