HOW TO KNOW THE IMMATURE INSECTS 



They have no resting stage (pupae) before the aduU is reached. The 

 body form and structures as well as the feeding habits are generally 

 similar to those of the adult. 



Fig. 18. Nymphs: a, grasshopper; b, pear psylla, Psylla pyricola Fors- 

 ter; (Redrawn from Conn. Agr. Expt. Stc. ) c, Western crick- 

 et, Anabrus simplex Haldeman; d, plant bug; e, AAallophaga; 

 f, Anoplura; g, aphid. 



In the Thysanoptera, there is no indication of wing pads until the 

 second or third instar. In Corrodentia, the nymphs lack wing pads 

 even in species that develop wings. In Thysanoptera and the male 



Fig. 19. Bean thrips, Hercothrips fasciatus (Pergonde): a, 

 egg; b, newly hatched nymph; c, mature nymph; 

 d, prepupa; e, pupa. (U.S.D.A.) 



Aleyrodidae and Coccidae, there is what appears to be a pupa. In 

 the male Coccidae, even a cocoon is formed. The nymphs of Noto- 

 nectidae, Corixidae, Belostomidae, Nepidae and some other smaller 

 families of Hemiptera are semi-aquatic. They descend beneath the 

 waters and remain there for a considerable period of time, out they 

 are air breathers. 



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