INSECT PESTS 227 



each side, one spine situated dorso-laterally, the other ventrolaterally. Posterior 

 margin of metathorax blunt. First two segments of antennae pale, the remainder 

 dusky. Average length 1 mm. 



Second instar. General color light yellowish green. Eyes losing some of their 

 red color. Posterior border of metathorax sharp in outline. First two segments of 

 antennae light yellow, remainder dusky. Average length 1.30 mm. 



Third instar. General color pale yellowish green. Eyes almost pearl white. Body 

 more robust than in first two stages. Wing pads appearing as lateral buds extend- 

 ing to the hind margin of the first abdominal segment. Spines darker and more 

 prominent. Average length 1.85 mm. 



Fourth instar. Head and thorax yellowish green; abdomen yellow. Eyes pearl 

 white. Wing pads extending to hind margin of second abdominal segment. Spines 

 prominent. Average length 2.1 mm. 



Fifth instar. Head and thorax pale green ; abdomen yellow. Wing pads extending 

 to, or nearly to, the hind margin of the fourth abdominal segment. First two antennal 

 segments green, remainder dusky. Body broader than in previous instar. Average 

 length 2.6 mm. 



Adult 



Pale green, usually with a row of white spots on anterior margin of pronotum. 

 Length 3.S mm. 



Vertex bluntly angled, a little longer on middle than next to eye and about one- 

 third wider between eyes than length at middle. 



Color. Yellowish to pale green, markings variable; vertex frequently with 

 pale or dark-green spots ; pronotum usually with a row of six or more pale spots 

 along anterior margin, sometimes missing or indistinct ; elytra greenish subhyaline. 



Female genitalia. Last ventral segment moderately produced and roundedly 

 truncated. 



Male genitalia. Valve produced and roynded or bluntly angled ; plates triangularly 

 tapered to pointed apices, which are frequently upturned; lateral processes of the 

 pygofers rounded on inner margins and broadened on apical half, then concavely 

 rounded to narrow attenuated tips, which are slightly curved inward; spines of 

 tenth segment broad, with tips narrowed and directed downward. This combination 

 of characters will distinguish Empoasca fabae from closely related species. 



Biology. Many studies have been made on the biology of potato leaf- 

 hopper on potatoes, beans and other crops, but none has been made on 

 peanuts except in the form of general observations. Beyer (IS) reported 

 the results of life-history studies of the insect on beans in Florida and 

 Poos (114) reported similar studies on cowpeas in Virginia. There like- 

 wise are rather comprehensive reports from other sections on the biology 

 of the insect (54, 1,41). 



The potato leafhopper apparently over-winters only in the Gulf-Coast 

 States where some breeding may occur throughout most of the winter. As 

 the weather becomes warm in the early summer it spreads northward and 

 causes damage to a variety of crops during the summer and fall. Cold 

 weather presumably destroys all stages of the insect except in its south- 



