44 P. W. WHITING. 



were produced 4 males and 12 females. Seven virgin daughters 

 produced 804 males, and one of these females when later crossed 

 to a son produced 34 males and 5 females. 



The Lancaster stock, upon which most of the work with 

 Hadrobracon has been done, was derived from a single parasitized 

 caterpillar found in my cultures of the Mediterranean flour-moth 

 at Lancaster in June, 1919. It is highly probable that the 

 caterpillar was stung by a single female which came in from 

 some bakery or grocery store near-by, as I had no cultures of 

 Hadrobracon at that time. Seven females were reared, showing 

 that the mother had evidently mated. These females, isolated 

 without males, produced only males which were crossed back to 

 their virgin mothers in order to obtain females. This stock has 

 been bred since that time and has shown considerable variation. 



It will be necessary to give only summaries of the typical 

 black-eyed Lancaster stock as the data is very extensive and 

 results in reference to other somatic variations and sex-ratio 

 will be published later. 



Fifty-three females, isolated as virgin, produced 5,948 males 

 and no females. 



Forty females, set with males, produced 3,944 males, no 

 females. 



One hundred thirty-five females, set with males, produced 

 7,270 males and 4,791 females. 



We may now give the entire summaries of the black-eyed 

 stocks, including two different stocks from Philadelphia, one from 

 Mifflintown, and one from Lancaster. 



From one hundred and thirty-five virgin females there were 

 9,242 males. 



From forty-nine females set with males there were 4,141 males. 



From one hundred and ninety-nine mated females there were 

 8,000 males and 5,729 females. 



I feel very certain that among all these wasps there were 

 none of the orange-eyed variety described below. The difference 

 between the typical black-eyed form and orange is so striking 

 and the eyes of the wasp are so large that such a variation could 

 not escape attention. Moreover the material bred was examined 

 with some care as one of the main purposes of the work was to 

 find genetic differences. 



