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fly was placed within about half an inch, the larva evidently measured 

 the distance and sprang up and backwards, seizing the fly from 

 above, describing in its spring from its pole just the quarter of a 

 circle. I next arranged the approach of the fly so that I could watch 

 the movements of the larva from the side of the glass jar. Bringing 

 my magnifier into focus qtiietly^ I saw that the larva was '' close- 

 hauled " in its zigzag position. I then moved the fly, which the 

 larva saw approaching, — at least, so I gathered from a slight alteration 

 of position as I moved the fly, which was seized the moment it came 

 within the striking distance. I held the fly, quietly pulling the thread 

 which I had attached to it. The larva would not release its hold, 

 and I was puzzled to know what held it in its hole, for the whole 

 thorax and first two abdominal segments were arched over on the 

 surface. After repeated failures I found that it was securely held in 

 by the two long curved spines on the fifth abdominal segment. These 

 were laised (as previously described), and driven deep into the side 

 of the burrow, forming perfect anchors, and defying the prey to 

 overcome the larva. The anal spines were also driven into the 

 opposite side, so as to give additional power of resistance. 



Believing that these larvae catch their prey on the wing, I watched 

 day after day until at last I had the pleasure of seeing a larva spring 

 up and catch a blow-fly as it flew across the hole. Since then I 

 have frequently seen them make unsuccessful attempts. Once I 

 had fed each larva with an earwig, which all appreciated, and most, 

 after shooting the whole skin away, sat at the top of their burrow 

 enjoying the bright sunshine. I found a large earwig, which I put 

 into the box, guiding it toward a large larva having a nap. This 

 earwig crossed toward the pitfall, and when halfway over was shot 

 up into the air a height of over a foot, turning several somersaults in 

 its descent, moving off with considerable alacrity. 



During October, on the approach of cold weather, the larva 

 descend, excavate the hole, which is filled in from the inside, the 

 larva remaining in a semi-dormant state through the winter, or until 

 March is nearly over. It then opens up the burrow, and lives on 

 the fat of insects. I once saw a large cabbage butterfly pinned to 

 the ground by one of these larvae ; and in spite of its wings it could 

 not free itself from the jaws of the anchored tiger. Another winter 

 of abstemiousness is passed, and once more the sunshine is enjoyed 

 until the end of July, when the now full-grown larva thinks a change 

 necessary, so descending to the bottom of its burrow, which is 

 frequently ten to fifteen inches deep, it excavates a large oval 

 chamber, which is generally horizontal, though I have found them 

 in a slanting position. This sepulchre is an inch and a half long 

 by three quarters in diameter. The sand excavated is carried up 

 and rammed into the vertical hole The larva then rests upon 

 its back, the head being towards the vertical hole. The larva is 

 supported and protected by the thoracic plate, and the protuber- 

 ance and spine on the fifth abdominal segment, the anal segment 



