PLANTS AND ANIMALS 



73 



most abundant at or near the surface. Among these aquatic 

 carnivores are certain small cousins (species of Aldrovandia] of 

 Venus' Fly-Trap, which are specialized in much the same way. 

 They are native to South and Central Europe, India, and Aus- 

 tralia. 



The Bladderworts (species of Utricularia, fig. 1067) are widely- 

 distributed ditch -plants, closely related to the Butterworts, and 



Fig. 1067. Bladderworts (Utricularia} 



represented in the British flora. They feed in part upon small 

 aquatic organisms, and catch their prey in little bladder-like traps 

 formed by modification of parts of the feathery leaves (fig. 1068). 

 Each of these snares is not unlike a large water-flea in shape, 

 and the resemblance is greatly increased by the presence of two 

 branching bristles at the free end. Here, too, is placed the small 

 opening into the bladder, guarded by a little transparent flap 

 serving as a door, which opens inwards with the greatest ease, 

 but prevents exit. Why little creatures should be attracted to 



