HABITS OF THE SPHEX. 133 



One of these insects had captured a spider, which was too 

 heavy to be carried through the air. The Sphex then dragged it 

 to a little bank, dropped it into the water, and perched upon it, 

 sitting there until it had been carried some distance down the 

 stream. Finding that the spider was sinking, the Sphex left it, 

 and sat on a straw, which was floating down the stream, still, 

 however, keeping company with its prey. After a while, the 

 spider struck against the shore, and the Sphex then grasped it 

 afresh, and tried to drag it along. The steep bank, however, 

 baffled all its endeavours, and at last the industrious creature 

 was obliged to leave the spider on the ground, and to go off in 

 search of another. 



The dark and sombre little bee called Mellinus arvensis is an 

 excellent example of the burrowers. This insect preys on 

 various flies, and packs away a large number of its victims in the 

 burrow. The flies which it chooses are all swift of wing, whereas 

 the Mellinus is rather a slow flier, so that it cannot take its prey 

 by open assault, but is obliged to trust to craft. In order, there- 

 fore, to obtain its victims, the Mellinus watches some spot where 

 flies most love to congregate, and walks to and fro as if it were 

 quite unconcerned. It continues to run about in this manner 

 until it comes close to a fly, when it springs upon the luckless 

 insect, trounces it in its claws, and carries it off like a falcon 

 with a partridge. 



Six or seven flies are generally taken by the Mellinus, and as 

 soon as the larva is hatched, it begins to devour the fly which is 

 nearest to the bottom of the cell. It eats them in succession, 

 usually devouring six of the victims, consuming the softer parts 

 only, and leaving the head, shell of the abdomen, part of the 

 thorax, and the limbs. Ten days suffice for the completion of its 

 feeding, and it then spins a tough, dark-coloured cocoon, wherein 

 it remains during the winter and part of the spring, changes 

 into the pupal condition in the summer, and attains its perfect 

 state at the beginning of autumn. 



Another species of burrowers, Oxybclus uniglum.is, has similar 

 habits. Mr. F. Smith writes of it as follows : " I once observed 

 several females running amongst the blades of grass which shot 

 up from the surface of a little hillock upon which the sun shone 

 and tempted various diptera, occasionally to alight. The Oxy- 

 beli continued to jun about, apparently unheedful of the flies, 



