298 



CHARLES ZELENY 



eye has an average of 810.6 facets in the females and 849.8 facets 

 in the males (tables 1 to 4). The unselected red-bar stock, as 

 obtained by Zeleny and Mattoon ('15) for their selection work, 

 has an average of 65.1 facets for the females and 98 for the males. 

 The unselected white-bar stock (nos. 144 and 145) which served 

 as the starting point of the selection line in which ultra-bar origi- 



TABLE 2 



Comparison of full eye, bar, and ultra-bar at 27°C. Males. The class distributions 

 in the same populatio7i are given in table Jj. and figure 3 



' With the small number of cases represented under full eye, the standard 

 deviation and probable error determinations of course have no great significance. 

 The values given are those obtained by following the usual methods employed 

 when larger numbers of cases are available. They may, however, indicate in a 

 very general way the probable variability of the stock as compared with the 

 others. 



^ Second low selected generation including all matings and excluding the 19- 

 facet male from which the ultra bar stock was derived. 



nated had an average of 58.8 facets for the females and 111.4 for 

 the males. In the white bar this represents a change of —26.67 

 factorial units in the females and —21.15 in the males, according 

 to the system of tabulation used in the present paper and de- 

 scribed briefly on page 309 and more fully in a separate paper 

 which is in preparation. A factorial unit is one that produces a 

 10 per cent change in facet number. 



