752 Tsabel McCracken 
of univolts therefore obtained. Of the 30 matings in series A’, 
two broods hatched or were bivoltin in1g06. Aratioof 14U:1B 
or go per cent of univolts obtained. 
For convenience of reference, these results may be tabulated 
thus. (See also “Table of Descent.”’) 
TABLE IT 
BROOD \ 
TOTAL | RATIO OF | 
CONDITIONS | NUMBER OF NUMBER OF | PER CENT 
NUMBER OF Brea | 
OF PARENTS BIVOLTS UNIVOLTS | or U 1906 
| | BROODS (1906) 
|AND LINEAGE | | 
ps See the a | | 
. | | | | 
Sams AG so sodoc —04 —05 | 30 2 28 Pe re Bayes | go+ 
a Series) Daciyesicereie | —o4 +05 | ° 26 Toe 86+ 
| 4. 
| 
Three points present themselves for consideration from a study 
of Tables I and II; first, relative potency of the bivoltin and 
univoltin in Series A’ and Series D, Table II; second, relative 
potency of these characters in Series B, Table I, and Series D, 
Table II; third, suppression of the bivoltin in Series A, and its 
expression in Series A.’ 
In regard to the first point; namely, relative potency as 
correlated with lineage in the expressicn of the characters, the 
data show that the larger percent ge of univolts obtains in the 
line of the greater suppression of bivolts. With reference to the 
second point, the small number of matings in Series B may 
account for the seeming prepotency of the bivoltin in 1905 (Table 
I) as against its subpotency in 1906, Series D, (Table II). It 
may be, however, that this prepotency obtains in first crosses of 
the hybrid uni-bivoltin cross through the female. ‘This point 
will be further tested. ‘The fact with reference to the third point 
is certain. Failure of the bivoltin character for two successive 
generations through the univoltin female (with a bivoltin male in 
1904 and a hybrid uni(bi)voltin male in 1905) does not preclude 
the possibility of its reappearance in the third generation (1906). 
It was determined at this time to utilize this material to its 
utmost advantage for a further study of heredity. 1 le 
