174 



MOSQ UI TO ERA DI CAT ION 



small piece of bark. The larva hovered over this piece of bark, and the 

 fish did not detect it. When it was placed in open water, without the 

 least protection, the fish swam around it, even 'nosed' it, while the larva 

 lay perfectly motionless. At last, a rather small minnow seized it and 

 swallowed it. Placed another larva in open water among fish. This 

 one too lay perfectly still, drifting like a small stick, while fish swam all 



Fig. 117.- 



(Photo by E. H. Magoon, C. E.) 

 Dipping up larvae concealed by dense vegetation. 



about it, nosing it a time or two, but apparently not detecting that it was 

 alive and something to eat. Finally, it drifted near a tuft of grass and, 

 with a surprisingly quick motion, it swam into the vegetation. It was 

 removed and placed in open water. There it lay motionless for about 

 5 minutes, when at last it was snapped up by an under-sized minnow. 

 "These feeding experiments, which were repeated many times, demon- 

 strated that the protective instinct in mosquito larvae is highly devel- 

 oped. It was shown many times that the only protection an Anopheles 

 larva has from fish in open water is inactivity. When the larva thus 



