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The Ohio Journal of Science [Vol. XVIII, No. 7, 



Five days after oviposition, a dark discoloration is noticed 

 on the parasitized nymph near the region where the ovipositor 

 is inserted. This is due to the presence of the developing par- 

 asite within the tissues, surrounded by its first exuvium, the 

 dull gray color of which shows through the opaque yellow body- 

 wall of the host. Thus it seems likely that the egg hatches 

 very shortly after being laid, and that the first instar is rel- 

 atively of short duration. Two days later, a week after ovipo- 

 sition, a tiny gray vesicle protrudes between the segments of 

 this nymph. This is the second larval instar enclosed within the 

 first exuvium. At this phase, the entire outlines of the parasite 

 can be seen within the body of the jassid, the anterior end 

 reaching as far anteriorly as the posterior margin of the pre- 

 ceding segment. 



The second molt occurs in from seven to ten days after the 

 appearance of the sac, and the third three to four days later. 

 The larva enters the fifth instar and kills the host eighteen or 

 nineteen days after the sac becomes external. Within a few 

 hours the host is devoured, and the parasite leaves it. The 

 nymphs are killed in from twenty-four to twenty-five days 

 after oviposition. 



The larval sac is about 1 mm. in width, oval, compressed 

 and dull black in color, being composed of the typical three 

 exuviae, the first being smooth and shining, the second dull and 

 roughened on the outer half, and the third being distinctly 

 rugosely sculptured. 



Immediately after emerging the white, grub-like larva seeks 

 the soil, beneath which it spins a compact oval, white cocoon 

 covered with soil particles. Some of the larvae in the second 

 generation spin their cocoons above the soil, attached to some 

 convenient object, a fact not observed in those of the first or 

 summer generation. The outer cocoon is completed in a day, 

 but longer time is required for the completion of the inner. The 

 larvae of the last generation can be seen spinning within the 

 cocoon for days after it is apparently completed. The length of 



