( V ) 



with blue like ab. semisyngrapha, the other hind-wing having 

 only a thin sprinkhng of blue scales over the same area; 

 taken at Eoyston, Aug. 1916. 

 Further Note dealing with the question of the 



SPECIFIC IDENTITY OF PeDICULUS CAPITIS AND PeDICULUS 



HUMANUS (vESTiMENTi). — Mr. Bacot read the following note : — 

 " At a previous meeting (see p. xiv, 1916), when referring to 

 this question, I suggested that the disparity in the propor- 

 tions of the sexes in the F. 1 generation resulting from a cross 

 pairing between a P. capitis <S and P. humanus ? lent support 

 to the view that these insects were distinct species. In a 

 subsequent conversation the Rev. James Waterston challenged 

 this view, on the ground that it was necessary to prove that 

 normal sex-proportion resulted from pairings within the two 

 races, a point I had taken for granted, owing to the parity of 

 the sexes in my stock boxes. I have now obtained details 

 of the sex-proportions of a number of broods of P. humanus, 

 which I propose to lay before you. Paired couples of P. 

 humanus were taken from a stock box, segregated in small 

 boxes, and their offspring reared to maturity, with the following 

 result : — 



No. of Pairs. 6 6 ? 9 



1 1= 2% 43= 98% 



2 44 = 49% 46= 51% 



3 31 = 65% 17 = 35% 



4 Nil. 67 = 100% 



5 119 = 73% 43= 27% 



6 39 = 66% 20= 34% 



7 116 = 68% 55= 32% 



8 Nil. 46 = 100% 



9 54 = 92% 5= 8% 



10 Nil. 49 = 100% 



11 10 = 71% 4= 29% 



12 Nil. 39 = 100% 



13 Nil. 48 = 100% 



14 7= 9% 74= 91% 



15 42 = 68% 20 = 32% 



463 = 45% 576= 55% 



