252 



Marvels of Insect Life. 



Photo bv] 



\H. Main. F.IC.S. 



entirely upon other Insects. Then, however, it does 

 not pursue its pre\' and hunt it down, but waits 

 patiently for its victims to come close to it. Like 

 the trap-door spider, the grub constructs a shaft in 

 the ground, from whose smooth, rounded mouth he 

 can watch for the coming of his victims. 



But let us begin at the beginning. The female 

 tiger-beetle is provided with a strong egg-laying 

 drill, with which she bores a hole in suitable soil. 

 Through the drill passes a single egg, which is left 

 at the bottom of the hole. She repeats this process 

 about fifty times. About a fortnight later the grub 

 hatches out. It looks a misshapen little creature, 

 its body being thrown into three curves. The head 

 and adjoining fore body are broad and flat, 

 forming a sort of shovel, and in addition to the six 

 legs there are a couple of hooks on the upper side of 

 the fifth segment of the hind-body. At first the little 

 pit dug by his mother is sufficiently large to house 

 him, and he is content with consolidating the walls 

 and rounding the mouth. As he grows he enlarges 

 the pit to suit the increase of his length and girth, 

 and he keeps a circular area around the mouth clear 

 of loose earth. In the operation of enlarging the shaft the shovel head comes in 

 useful for carrying the surplus earth up to the surface, and the curves of the body 

 and the hooks on the back make climbing easy, as well as enabling him with comfort 



to remain on watch at the top of the pit-shaft. In 

 this position the flat head forms a stopper to the 

 shaft, whilst the position of the eyes enables a good 

 watch to be kept upon the surrounding area. In this 

 matter of waiting for its dinner to come to it the tiger- 

 grub is much like the ant-lion, except that it watches at 

 the top of its pit, whilst the other waits at the bottom. 

 No small animal walking carelessly over the ground 

 could suspect anv danger ; so it is seized by the terrible 

 jaws, and is then taken to the bottom of the pit to be 

 demolished in private. 



The pit of this and most other species is vertical 

 or at right angles to the surfacc\ whether that surface 

 is horizontal, perpendicular, or sloping, in one of 

 our British species ^ it is curved. The shafts var}' in 

 depth according to species and the nature of the soil. 

 That of our common species, when the grub is full- 

 grown, may be a foot deep. When about to change 

 its skin, the i^rub closes the mouth of its shaft and 



The Grub of the Tiger-Beetle. 



In its larval stage the tiger-beetle is as fully 

 deserving of its name as in the perfect state. 

 The terrible jaws are already a striking feature, 

 and the plump condition of the hind-body shows 

 that they are used to good purpose. In both 

 these conditions the tiger preys upon other 

 Insects. The photograph shows the grub three 

 times the natural size. 





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fhoto by] III. Main, F.K.H. 



The Tiger's Climbing Hooks. 



In this photograph a portion of the hind- 

 body is further enlarged to show the pair of 

 climbing hooks by whose aid the grub makes 

 rapid ascents and descents in its burrow. The 

 view is from the side, and is four times the 

 natural size. 



' Cuindt'la h\l)i"icla. 



