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The Ohio Journal of Science [V^ol. XVIII, No. 7, 



Haplogonatopus americanus Perkins. 



Nearly mature nymphs and adults of Liburnia campestris 

 and L. Lutulenta are found bearing the larval sacs of Haplo- 

 gonatopus americanus throughout the latter part of July and 

 early August in the vicinity of Sandusky, Ohio, and in June and 

 August about Columbus, Ohio. L. campestris is by far the 

 more heavily parasitized species of the two, possibly due to its 

 greater abundance. The larval sac of this parasite is always 

 dorsal in position and attached to the posterior region of the 

 host's abdomen. The greater number of sacs are found pro- 

 truding between the 5th and 6th segments, but there is some 

 variation as the following table shows : 



Unlike the other two species studied the females do not 

 oviposite readily in captivity and so but few data were obtained 

 in the oviposition experiments. At the time the adults issued 

 nearly all the Liburnias had matured and there is a possibility 

 of this species living until a second generation of nymphs is 

 produced. This is not likely since this species parasitizes adults. 



The process of oviposition was observed in a few instances 

 and is similar to that already described for Gonatopiis erythrodes 

 (Perkins), except that the tip of the ovipositor is curled upward 

 and thrust in the dorsal side of the abdomen. Parasitized hop- 

 pers taken in the field bearing sacs containing larvae in the 

 second instar are killed by the mature larva within eight to 

 eleven days. 



When the larval sac becomes visible on the outside of the 

 body of the host, it is dull grey or brown in color but when fully 

 developed it is brown or dark yellow. It is then 1 mm. in 

 length and oval in shape. The first exuvium is smooth and 

 shining and is always darker in color than the other two. These 

 comprise the greater part of the sac and are dull and roughened. 

 The spiracles are dark brown and distinctly visible along the 

 median line of the different exuviae. 



After leaving the host the white elongate larva almost imme- 

 diately starts spinning the cocoon on some convenient object 

 above the ground. The cocoon is completed in two days and is 



