INHERITANCE IN HYDATINA 



71 



ten daughters was bred the parthenogenetic Hne H2 (table 24). 

 It included 20.2 per cent of male-producers. 



^3. Females of the parthenogenetic line Ho were paired with 

 males of the same line March 29 to April 7, 1912. From 42 

 such females, 640 eggs were obtained, of which 407, or 63.5 per 

 cent, hatched before April 30 (table 25). The low viability lot 

 L3 hatched, at about the same time, only 39.2 per cent. 



TABLE 25 



Showing number of fertilized eggs that hatched, out of 64O in lot H3, figure 1 



Percentage of viable eggs. 



63.5 



From the 42 females that laid the eggs in lot H^, two were 

 selected for further breeding. One laid 16 eggs, of which but 

 7, or 43.7 per cent, hatched; the other laid 21 eggs, of which 

 17, or 80.9 per cent, hatched. From the first daughter of each 

 was bred a parthenogenetic line, as given in table 26. The pur- 

 pose was to test the effect of selection within the high viability 

 series, the results of which are described later. The first of these 

 lines included 10.0 per cent, the second 11.1 per * cent of 

 male-producers. 



. The percentage viabihty of the eggs in lots Li, L2, and L3 

 were 28.9, 35.3, and 39.2, respectively; in lots Hi, H2, and H3, 

 it was 52.3, 49.3, and 63.5, respectively. The high viability lots 

 were consistently more viable than the lots selected for low via- 

 bility. With the exception of the second lots, the difference 

 between the two lots is nearly constant; and this exception is 

 probably due to the fact that L2 and H2 were not hatched at the 



