THE ASILUS. 357 



one of the largest of our British Diptera^ the Asilus 

 crabroniformis, which is found abundantly in mea- 

 dowSj and occasionally in gardens. It is of an elon- 

 gated form^ with the extremity of the abdomen 

 pointed ; it usually measures about an inch in length, 

 and is of a tawny colour_, with the eyes and first three 

 segments of the abdomen black, and a brown band 

 down the centre of the thorax. The wings are tawny, 

 spotted with brown along the hinder margin. This 

 fine insect may be found in abundance in the hot 

 days of summer, flying rapidly over the herbage with 

 a humming noise when on the look-out for its prey, 

 which consists for the most part of small Dipterous 

 insects; these it seizes with its fore-legs, and speedily, 

 sucks out, by means of a most formidable-looking 

 black proboscis, which projects like the beak of a bird 

 from the lower part of its head. So powerful is this 

 organ, that De Geer states he has seen one of these 

 insects pierce through the elytra of a Lady-bird ; and 

 Kirby and Spence mention having observed them 

 with various beetles, including a Hister, applied to 

 their mouths. They are said also to wound the 

 fingers of their captors if incautiously handled, and 

 sometimes to attack cattle and suck their blood. 



A vast number of small flies belonging to the 

 genera Empis, Dolichopus and their allies, agree 

 closely with the Asili in their habits, and notwith- 

 standing their comparatively diminutive size, are as 

 actively predaceous as their gigantic relatives. Of 

 the Empides many species are abundant about woods 

 and hedgebanks, where the males feed upon the nectar 

 of flowers, and the females constantly pursue the prey 

 which furnishes them with a more nourishing food. 

 Even in their amours, indeed, these little gluttons 



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