Banded Flea-beetle 

 Potaio Flea-beetle Three-spotted Flea-beetle 



LIFE HISTORY 



The life history of this beetle is imperfectly known. It is thought 

 that the winter is passed in the larval stage only. The adults are most 

 numerous in June and July, during which months mating and egg laying 

 take place. There is no positive evidence of a second brood. 



(c-2) POTATO FLEA-BEETLE 



(Fig. 5, Plate IV, Page 17) 



Not infrequently swarms of the potato flea-beetle appear in fields of 

 sugar beets, causing considerable damage to small areas. At such times 

 the injury to the crop is similar in every way to that caused by the striped 

 flea-beetle and the same remedies should be applied. 



This insect's liking for potatoes is- indicated by its common name 

 "potato flea-beetle," while its habit of attacking cucumbers and related 

 plants suggested the second part of its scientific name, "cucumeris." 



DESCRIPTION 

 The Larva 



The larvae are small, whitish grubs which feed in the roots of several 

 common wild plants all belonging to the same family as the potato. The 

 roughened condition of potatoes known as "pimply" potatoes is caused 

 by the larvae burrowing into the tubers. 



The Adult 



The adult beetles (Fig. 5, Plate IV, Page 17) are a dull black with 

 the exception of the legs and antennae, which are yellowish. The wing 

 covers are clothed with very fine hairs and their surface is covered with 

 small punctures which are arranged in rows. The thorax has a deep, 

 curved depression across the posterior margin, as shown in the figure. 

 The small outline drawing at the left of the figure is the natural size of 

 the adult. 



LIFE HISTORY 



The eggs are deposited on the roots- of the host plants during May 

 and June by the adult beetles, which have spent the winter in hibernation 

 under dead leaves and other trash along ditch banks, fence rows and 

 roadsides. 



The larvae tunnel into the roots of the host plants, where they feed 

 until fully grown. The mature larvae form small, oval cells in the soil, 

 near the roots of the plants within which they fed, and change to pupae. 



(c-3) THREE-SPOTTED FLEA-BEETLE 



(Fig. 6, Plate IV, Page 17) 



The three-spotted flea-beetle. (Fig. 6, Plate IV, Page 17) is conspicu- 

 ous in beet fields in early spring mainly because of its size and coloring. 

 It is one of the largest flea-beetles and is readily distinguished by the 

 yellowish-red thorax bearing three black spots. 



Lamb's-quarters and related plants, such as Russian thistle and sugar 

 beets, appear to be favorite food plants of this species. 



Seldom, if ever, does this beetle occur in great enough numbers to 

 require the application of remedial measures. 



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