DETERMINATION OF SEX OF PEDICULUS VESTIMENTI. 387 



these were dissected as stated above and their sex determined. 

 Of these 27 were males and 15 females. 



For the first half of the experiment the females were more 

 numerous than the males; the proportion of males then gradually 

 increased until the final result gave 62 males and 53 females. 



These results are of value only because the sex was determined 

 for 92 per cent, of the entire generation, but the experiment must 

 be repeated many times before the evidence can be of scientific 

 value. 



