COCOON OF THE ANT LION. 369 



work, proceeding backward, and shovelling the sand exactly as 

 described, but only in irregular lines, leaving one after it had 

 proceeded for some distance, and beginning another; so that 

 they did not make even one complete circle. I was called to 

 a distance, however, and the insects were thrown away. The 

 species was probably M. Leachii, of which I have taken a 

 single specimen near Bluefields — the only one I ever met with 

 in a perfect state. 



" This rarity of the imago, contrasting with the abundance 

 of the larva, of this insect, has been noticed by Guilding in 

 St. Vincent's. He observes that not a single perfect insect 

 had been found by him in a state of liberty, though the larvae 

 swarm under every rock or shed calculated to protect their 

 pitfalls from the rain and wind." 



In this genus the antennae are extremely fine and are knobbed 

 at their tips, so as to bear a close resemblance to the antennas of 

 butterflies. When the insect is at rest it assumes a very singular 

 attitude, depressing the wings and elevating the abdomen at a 

 considerable angle, so as to harmonize in outline with the twigs 

 among which it sits. 



When the Ant Lion larva is full-fed, it encloses itself in a 

 beautifully made cocoon formed from sand-grains fastened to 

 each other with fine silken threads. The walls of the cocoon are 

 very slight, and the interior is lined with silk. Considering the 

 size of the perfect insect, the length of its abdomen, and the 

 wide spread of its wings, the dimensions of the cocoon are very 

 small, the diameter rarely exceeding half an inch. As, how- 

 ever, is the case with insects in general, the wings are not 

 expanded until they have been exposed to the open air ; they 

 are easily contained in the diminutive cocoon. 



Still, though we can thus account for the wings, we cannot for 

 the dimensions of the body, which is about an inch and a half in 

 length when the insect is fully developed. The wonder is not 

 decreased if the cocoon be opened, for the enclosed pupa will be 

 then seen to be very small, scarcely half an inch in length, the 

 legs and immature wings folded on the breast. In order to 

 understand the manner in which this curious problem is solved, 

 we must watch the creature as it escapes from the cocoon. 



The pupa is furnished with a pair of broad, short, stout, saw- 

 edged mandibles, not the least like the sickle-shaped jaws of the 



B B 



