AN SPTEROUS MUTATION IN HRt < 111 S. l6j 



a ( -on< hision. However, in the tests which follow, it i- demon- 

 strated that the genes are carried by both sexes, but are visible 

 only as phenotype- in the females. The trait i- therefore sex 

 limited. If this i- true, the character could ha\ . inated 

 P' >--ibly in the male previously but remained unseen. A recessive 

 niutaii>.ii. like apterous, could not be seen in either >e\ until the 



lion after its mutation. This i> tin- probable orij 

 and accounts tr the seven apterous in-ert- diseosered in the 

 -.inic ^cm-ration. 



I ach apterous Brnchns was mated to a normal \\in-ed brother 

 trom a -ionl North C'arolina culture. Se\ en pairs in .ill \seiv 

 mated r.iblr I.), but only two produced \ \. pairs 2 and <.. 



Pair 2 in the I : generation produced 4 normal winded fein.ile> and 

 5 noniial uin^ed males. These were inbred as a ma culture in 

 the I . .is ing 13 winded females, 2 apterous female-, and 11 

 uin^ed males. The two apterous females were mated \\ith an 



winged male from this same fraternity but no oi'f-priiu \ 

 IOIIIK!. I 'air 6 was the other of the seven apterous in-e< t- \\ Inch 

 had pro-en\ They produced in the FI 9 win^il It male- and s 

 \\iirced male-. These FI beetles were inbred .1- a ilnnv. 



Their ] v consisted of 9 winged females, .> apterou- female-, 



and u uin^eil males in the Fj. Kach of tlie-e three 1 . aptenm- 

 tles was mateil with a male from the same fraternity, but no 

 .ens s\.:- found from any pair of the three Vgain from 

 thi- -ame I . fraternity 6 winged females wen- bred to tise \\ii 

 male-. I IMA produced in the F 3 7 winged tem.ile- .; apit KHI- 

 lemale-, and < winged males. Another winged pair from tin I 

 gave i:se s\ in^ed females and two winged male-* in the I-".. The 

 la-t t\\o of i he \ : -> females were mated \\ith the laM 5 \\in 

 males < if this same fraternity. They produced in the l : 3 6 

 s\ini;ed female-. 4 apterous females, and 12 winded male-, l.aeh 

 of the-e four. 1 :! , apterous was bred with a winded male from a 

 wild (iilture, the same North C'arolina -lock but only ts\o pairs 

 uas e oft -prin- in a mass culture consisting of 8 winged females and 

 7 \\inged male- in the FI generation. The-e bred in ma-- 

 prodnred _\S \\in;^ed females, 4 apterous females, and .v \\ii [ 

 males. This apterous trait came to an end \\hen e.n h of the-e 

 four wingless female- ssere each mated with a male from a North 

 t'arolina enltiire from the experiment table. The apterou- 



