INTERRELATIONS OF PLANTS AND ANIMALS 31 



Another group of insects sometimes found on flowers in tli<> fall 

 are flies. They belong to the order Diptera (two wings). These 

 insects are usually rather small and have a single pair of gauzy 



Forms of life to be met on a field trip. .4, The red-legged locust, one of the 

 Orthoptera; o, the egg-layer, about natural size. B, the honey bee, one of 

 the Hymenoptera, about natural size. C, a bug, one of the Hemiptera, about 

 natural size. D, a butterfly, an example of the Lepidoptera, slightly reduced. 

 E, a house fly, an example of the Diptera, about twice natural size. F, an 

 orb-weaving spider, about half natural size. (This is not an insect, note the 

 number of legs.) <?, a beetle, slightly reduced, one of the Coleoptera. 



