K. Pkarson and A. Lkk 



3()3 



il 



DiAoiuji JI. I'idhiilih' Spiiii (if DaiKjliler fiir ijitwn Motlicr'.i Spun. 

 RpKvessioii Line: D = iilS+iT3M. 1370 Cases. 



63 63 e-l 55 59 57 58 59 60 61 63 63 64 65 66 67 «8 69 70 71 73 



Blotlur's Sjxin { = M) in iiiclies. 



Diagram III. Probahle Span of Sister for given Foreanii in llmtlin: 

 Regression Line: S = 39 '66 + 1-280 B. 1399 Cases. 



17 18 19 30 



Forcarm of lirolher { = B) in inrhcx 



