VARIATION AND MENDELIAN INHERITANCE 



399 



each cas e, by multiplying the original standard deviation by the 

 factorv''l-r-, in which r is the correlation between body length 

 and the character in question. ^^ 



(^HYBRIDS 



M<sn 95.1 



Fi HYBRIDS 



Mean 37.3 



Jl 



nrU h F HYBRIDS 



Mean 37. 2 



CARLOTTA 



Mean 41.6 



^ 



J^Ji 



rn 



CALISTOCA 



Mean 34.5 



TAIL% TAIL STRIPE 



Fig. 6 Histograms permitting comparison of variability of the parent races 

 and the Fi and F2 generations of hybrids, with respect to relative tail length and 

 tail stripe, in the Carlotta-Calistoga cross (sexes combined). Shaded squares, 

 in pure races, indicate parents of Fi broods. Shaded squares in Fi indicate 

 parents of Fo broods and sibs of same. 



A brief analysis of these figures has been made in the intro- 

 ductory section of this paper. No further discussion of them 

 seems worth while at the present time. 



28 This gives the same result as if each single deviation for the character in 

 question were corrected by making allowance for its correlation with body length, 

 as was done for the mean values in table 1. For this and certain other information 

 of a mathematical nature I am indebted to my colleague, Dr. G. F. McEwen. 



