In order to obtain more accurate information on the location of facet, a facet male was mated to an eosin vermilion female. The F_1 females were mated singly to wild males and they gave the results shown in table 60. The F_2 females were not counted, since they do not furnish any information. The evidence of table 60 places facet at 1.1 units to the right of eosin, or at 2.2.
TABLE 60.--_P_1 eosin vermilion_ [female] × _facet_ [male]. _F_1 wild-type_ [female] × _wild_ [male].
+----------+-----------------+-----------------+-----------------+ | | w^c v | w^c f_a | w^c | | | ------- | --+---- | ----+- | | | f_a | v | f_a v | |Reference.+----------+------+------+----------+------+----------+ | |Eosin |Facet.|Eosin |Vermilion.|Eosin.|Facet | | |vermilion.| |facet.| | |vermilion.| | | | | | | | | +----------+----------+------+------+----------+------+----------+ | 512 | 43 | 43 | .. | 1 | 13 | 16 ~ | 513 | 28 | 35 | .. | 2 | 19 | 5 ~ | 514 | 18 | 31 | 1 | .. | 17 | 11 | | 515 | 18 | 60 | .. | .. | 20 | 15 | | 516 | 10 | 31 | .. | .. | 7 | 12 | | 517 | 24 | 34 | .. | .. | 10 | 12 | | 518 | 44 | 38 | 1 | 1 | 23 | 22 | +----------+----------+------+------+----------+------+----------+ | Total.| 185 | 272 | 2 | 4 | 109 | 93 | +----------+----------+------+------+----------+------+----------+
+----------------+------+----------------------------+ | w^c f_a v | | | | --+---+-- | | Cross-over values. | | | | | +----------+-----+Total.+------+----------+----------+ |Eosin |Wild-| |Eosin |Facet |Eosin | |facet |type.| |facet.|vermilion.|vermilion.| |vermilion.| | | | | | +----------+-----+------+------+----------+----------+ ~ .. | .. | 116 | .... | .... | .... | ~ .. | .. | 89 | .... | .... | .... | | .. | .. | 78 | .... | .... | .... | | .. | .. | 113 | .... | .... | .... | | .. | .. | 60 | .... | .... | .... | | .. | .. | 80 | .... | .... | .... | | .. | 1 | 130 | .... | .... | .... | +----------+-----+------+------+----------+----------+ | .. | 1 | 666 | 1.05 | 30.5 | 31.3 | +----------+-----+------+------+----------+----------+
The third of the lethals which Miss Stark found (Stark, 1915) while she was testing the relative frequency of occurrence of lethals in fresh and inbred wild stocks arose in April 1914 in stock caught in 1910. Females heterozygous for this lethal, lethal _sc_, were mated to white males and the daughters were back-crossed to white males. Half of the daughters gave lethal sex-ratio, and these gave 1,405 cross-overs in a total of 3,053 males, from which the amount of crossing-over between white and lethal _sc_ has been calculated as 46 per cent.