48 



Marvels of the Universe 



which it is walking 



and decides at once to return. Now, although it may with caution travel 

 downwards over the sand spread so smoothly by the larva, yet to turn round, or climb upwards, is a 

 very different matter, for the sand immediately begins to roll down the banks. 



The moment the sand commences to fall, the ant-lion is alert, quickly hurling showers of sand 

 up the banks, and before the ant realizes what has happened, it finds itself slipping down the sides 

 of the pit. It is at once seized by the formidable jaws of the grub, from which there is no 

 escape, for these organs act like suction-pumps, absorbing the juices of the prey while they hold it. 

 A large spider, or a beetle, when entrapped, proves a more troublesome captive, and if, before 

 it is seized, its struggles bring down sufficient sand to allow it to climb out of the pit, it may escape ; 

 it is, however, a lucky insect that survives a visit to the ant-lion's den. 



When the meal is finished, the ant-hon pitches the shrunken skin of its victim well beyond the 

 borders of its excavation, probably to prevent future victims from taking alarm. It then proceeds 

 to repair the damage to its retreat, and again goes into ambush. 



The common species here described is found both in Southern France and in Switzerland, but 

 does not occur in Britain. There are some three hundred species of ant-lions known to science, 

 of which America claims at least thirty ; so that they constitute a well-distributed group of insects. 

 It should be mentioned, however, that all the species do not dig pitfalls, and, also, that many of 

 them progress in the usual direction when walking. Probably when more is known of these insects 

 the backward movement will be found to be associated with the pit-making habit. Those species 



which construct no pits have to capture 

 their prey by hiding in suitable spots until 

 a victim approaches. 



The duration of the life of the larva 



depends largely on the food supply, and it 



may spend two years as a hunter in the 



\ M grub state. It then spins a circular cocoon 



in the sand, in which it changes to a pupa, 

 or chrysalis. In due course it bites a hole 

 in the cocoon and emerges above ground as 

 a winged insect, much larger than the 

 original grub, and, as previously observed, 

 resembles a dragon-fly, from which it can 

 be readily distinguished by means of its 

 clubbed antennas. 



VEGETABLE INSECTS 



rh"ln hjj-\ 



IE. -SV--^, F.L.S. 



THE VEGETABLE CATERPILLAR. 



The caterpillar of a New Zealand moth falls a victim to a 

 fungus which kills and feeds upon it. then shoots out a Ion:r stalk 

 upon which its spores are produced. 



BY EDWARD STEP, F.L.S. 



Under the name of the Vegetable Cater- 

 pillar, one of the products of New Zealand 

 has long been regarded as among the mar- 

 vels of natural history ; but when its real 

 nature is understood, it is seen to have 

 rather less claim to be so considered than 

 many everyday phenomena that escape 

 attention. Of course, the imagination is 

 fired by the thought of a large caterpillar 

 walking about with a plant three times 

 its own length growing out from behind its 



