THE ANIMAL KINGDOM 431 



Order Coleoptera (Sheath-winged). Beetles. When at rest 

 the thickened anterior pair of wings, known as elytra, form 

 covers for the posterior membranous wings. Mouth parts are 

 for chewing, and metamorphosis is complete. 



Examples: Dytiscus marginicollis, diving beetle; Coccinella 

 novemnotata, ladybird beetle; Photinus scintillans, firefly; 

 Leptinotarsa decemlineata, potato beetle; Calosoma scrutator, a 

 common ground beetle with conspicuous iridescent coloring; 

 Tenebrio molitor, mealworm beetle. 



Order Lepidoptera (Scale- winged). Moths and butterflies. 

 The two pairs of membranous wings are covered with overlap- 

 ping scales. Scales also cover the body, legs, and appendages. 

 Mouth parts are for sucking. Metamorphosis is complete. 

 Usually moths have feathered or threadlike antennae and hold 

 the wings horizontally or wrapped around the body when at 

 rest. Most moths are nocturnal. The antennae of butterflies 

 and skippers as a rule are threadlike and knobbed at the ends. 

 At rest the wings are held together in a vertical position over the 

 body. They fly in the daytime. 



Examples: Samia cecropia, the large cecropia moth; Actias 

 luna, luna moth; Protoparce quinquemaculata, a hawk moth, 

 whose large green larva is known as the tomato or tobacco 

 worm, depending upon which plant it is feeding; Porthetria 

 dispar, the gypsy moth; Bombyx mori, the silkworm moth; 

 Papilio polyxenes, common swallowtail butterfly; Pieris rapae, 

 cabbage butterfly; Epargyreus tityrus, silver-spotted skipper. 



Order Diptera (Two-winged). Flies. The anterior wings are 

 large and membranous; the posterior wings are reduced to a 

 pair of knobbed threads, the halteres. Anterior wings are 

 sometimes lacking. Mouth parts are for sucking, and meta- 

 morphosis is complete. 



Examples: Anopheles quadrimaculatus, a mosquito, the female 

 of which transmits malaria; Glossina palpalis, tsetse fly that 

 transmits African sleeping sickness ; Musca domestica, housefly ; 

 Braula caeca, bee louse, a wingless form parasitic on the thorax 

 of queens and drones of the honeybee; Melophagus ovinus, the 

 sheep tick, wingless. 



Order Siphonaptera (Tube, Wingless). Fleas. Wingless insects 

 with the body compressed laterally; mouth parts for piercing 

 and sucking; legs for leaping. Metamorphosis is complete. 



