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JOURNAL OF ECONOMIC ENTOMOLOGY- 



\Yo\. 8 



Table 1. Showing the Average Percentage of Parasitism at Manhattan, 



K-^ys^SAS, IN 1914 



Month No. of Eggs Per Cent of Parasitism- 



May 3,002 0.16 



June 1,204 5.2 



July 4,989 . 6.3 



August 1,777 9.0 



September 28 25.0 



Collections of eggs were made in sixteen localities in the state during 

 July and August and the average parasitism for the state exclusive of 

 Manhattan was 14.5 per cent. 



The Egg 



Description. — Fully developed eggs were readily dissected from 

 the abdomen of the adult female and in a number of instances eggs 

 were dissected from the host egg soon after oviposition. The egg 

 (Fig. 11, A) is ovate in shape and tapers into a long stalk at one 

 end. The opposite end tapers gradually and ends in a blunt point. 

 The stalk is about two-fifths of the entire length of the egg and the 

 micropyle is located at its tip. The comparatively large nucleus is 

 located near the blunt end. The egg is 0.23 mm. in length and 0.07 

 mm. in width. 



Development. — -Shortly after deposition the egg begins to swell 

 due to embryonic development. In one instance an egg was removed 

 four hours after deposition. It had increased in volume, had become 

 spherical in shape and the protoplasmic content had begun to appear 

 differentiated but had not developed sufficiently to show anj^ definite 

 form. 



Length of Egg Stage.- — -The length of the egg stage was determined 

 in a number of cases and was found to vary from a few hours to about 

 one day. During midsummer eggs deposited about 6.00 p.m. hatched 

 before 7.00 the following morning. 



The Larva 



Description. — In the life history two distinct larval stages were 

 found. The first stage (Fig. 11, B) resembles closely the first 

 larval stage of Teleas as described by Ganin.^ The larva when first 

 hatched is about one-fifth the size of the host egg. It is supplied ^\dth 

 a large pair of mandibles which are strongly chitinized and each bears 

 a sharp claw at the outer extremity. The caudal extremity ends in 

 a long tail-like process which is about one-half of the length of the 

 body. No segmentation was distinguished but there is a marked 

 constriction between the head and the body region. 



^ Ganin, M., 1869. Beitrage zur Erkenntniss der Entwickelungsgeschichte bei 

 den Insekten. Zeits. wiss. Zool., bd. 19, pp. 381-451, 4 taf. , 



