April, '14] MCCOLLOCH: CHINCH BUG PARASITE 221 



the grasslands where they pass the winter in the clump-forming grasses. 

 The period of oviposition of the adults occupies the entire summer and 

 with the exception of a week or two in July, eggs may easily be found 

 in the field from the last of April until the first of October. 



The Egg of the Parasite 



Description — The eggs of the parasite have never been observed 

 after they were deposited in the host's egg. Ovarian eggs or ova were 

 examined many times. There never were found more than thirty 

 ova in a female and these were grouped together in the ovary, their 

 blunt ends towards the apex of the ovary and their tail-like portion 

 bent around in every direction. Judging from the comparative size 

 of the ova, the matured ovum is spatulate in shape with ovate body 

 which tapers into a long stalk. The opposite pole tapers gradually 

 and ends in a blunt point. The ovum, on an average, measures from 

 .07 to .09 mm. in length and from .02 to .03 mm. in width. The 

 stalk is about two fifths of the entire length and is slender and cylin- 

 drical. The micropyle is located at the tip of the stalk. The ovum 

 is nearly transparent and the granular character of the cytoplasm is 

 plainly visible. The nucleus, which is comparatively large, is located 

 as a rule near the blunt end of the ovum. 



Length of Egg Stage — So far it has not been possible to find the 

 egg of the parasite in the host, and so the exact length of the egg stage 

 has not been determined. However, the very young larva has been 

 found shortly after it has hatched, and thus the time between oviposi- 

 tion and the time the young larva was first seen varies from two days 

 to about a week. 



The Larva of the Parasite 



Description — Since it has not been possible to get the larva of the 

 parasite out of the host's eggs, a detailed description cannot be given 

 at this time. Looking at it through the shell of the host it appears 

 oval in shape and the segmentation is very indistinct. As the larva 

 grows the body contents become plainly visible. 



Length of Stage — The length of the larval stage varies with the 

 climatic conditions. Although during the summer the growth is very 

 rapid and the stage may be passed in from five to seven days, it may 

 range from ten to fifteen days. Li one case a larva shortly after hatch- 

 ing measured .12 mm. in length and nine hours later it measured almost 

 .6 mm. The growth of the larva occurs practically altogether during 

 the day time. 



Feeding of the Larva — Just how the food enters the larva has 

 not been determined, but after it gets within the body it is constantly 

 churned back and forth by contractions of the body. These contrac- 



