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LERP INSECTS. 

 .FAMILY PSYLLIDiE. 



Lerp insects are sometimes called ''jumping 

 plant-lice.*' The term ''psyllidae" comes from 

 psylla, a flea, from the jumping habits of these 

 insects. The adults strongly resemble miniature 

 cicadas, and vary in size from a sixth to a quarter 

 of an inch in length. (Plate 49, Fig. 8.) They can 

 be seen better with a lens. These are well worth 

 looking at, for they are dainty little creatures like 

 ''fairy cicadas.'' They live by sucking the juices of 

 plants, and, if present in great numbers, may become 

 a pest. 



The eggs are deposited on leaves, and stand erect 

 or slightly inclined (Plate 49, Fig. 5), for they are 

 fixed firmly on to the leaf. The larv« (Plate 49, 

 Fig. 6) appear and are similar in form to the adults, 

 but are smaller and have no wing-pads. Later, as 

 development goes on, wing-pads appear. (Plate 49, 

 Fig. 7.) The adult is winged. (Plate 49, Fig. 8.) 



In some species the larvae cover themselves with 

 a white, sugary scale, which is formed from a 

 fluid secreted by the insect. This fluid hardens to 

 form a brittle scale (Plate 49, Fig. 4) : seen with a 

 lens this scale is very beautiful. Some are said to 

 secrete a fleecy exudation under which they live; 

 while others make galls — some of a clear red colour 

 ^-and when these galls open at the top and are 



