Mat 19, 1911] 



SCIENCE 



787 



(1909) two of these white cocooners produced 



(1910) 35 white cocoons and no yellows. 

 Mating (1909) two yellow cocooners produced 

 24 yellow cocoons and no whites. Mating 

 (1908) another pair of F^ yellow cocooners 

 produced (1909) 9 white cocoons and 20 yel- 

 low cocoons. Mating (1909) two of these 

 white cocooners together produced 25 white 

 cocoons and no yellows. Mating (1909) two 

 of the yellows together produced (1910) 12 

 white cocoons and 21 yellow cocoons. Mating 



(1908) another pair of yellow cocooners from 

 the original Fj lot produced (1909) 4 white 

 cocoons and 17 yellow cocoons. Mating 



(1909) two of these yellow cocooners together 

 produced 8 white cocoons and 20 yellow co- 

 coons. Mating (1908) a yellow cocooner and 

 white cocooner of the original Fj lot pro- 

 duced (1909) 12 white cocoons and 12 yellow 

 cocoons. Mating (1909) two of these white 

 cocooners produced 19 white cocoons and no 

 yellows. Mating (1909) two of the yellow 

 cocooners produced (1910) 10 white cocoons 

 and 17 yellow cocoons. Mating (1908) another 

 yellow and white pair produced (1909) 16 

 white cocoons and 20 yellow cocoons. Mating 



(1909) two of these white cocooners produced 



(1910) 6 white cocoons and no yellows. Ma- 

 ting (1909) two yellows produced (1910) 8 

 white cocoons and 6 yellow cocoons. Mating 

 (1909) a yellow and a white produced (1910) 

 4 white cocoons and 12 yellow cocoons. Ma- 

 ting (1908) another yellow and white pair 

 produced (1909) 5 white cocoons and 31 yel- 

 low cocoons. Mating (1909) two of these 

 whites produced 19 white cocoons and no 

 yellows. Mating (1909) two of the yellows 

 produced 9 yellow cocoons and no white co- 

 coons. 



In 1907 a Bagdad "White female was mated 

 with an Istrian Yellow male from 9 :45 a.m to 

 11 A.M. and then with a Bagdad White male 

 from 11 A.M to 12:15 p.m. This mating pro- 

 duced 41 white cocoons, many of them creamy 

 white instead of the pure or faintly greenish- 

 white characteristic of the Bagdad white race. 

 Mating (1908) two of these white cocooners 

 produced (1909) 59 white cocoons. And 

 mating (1909) two of these F, white cocooners 



produced (1910) a small all white lot. Simi- 

 lar F, and F^ all white lots were obtained 

 from another Fj mating. Mating (1908) 

 another pair of F^ white cocooners produced 

 (1909) 46 white cocoons and 15 yellow co- 

 coons. Mating (1909) two of these white 

 cocooners produced (1910) a small all white 

 lot. Mating (1909) two of these F, yellow 

 cocooners produced (1910) an all yellow lot. 



In 1907 a Bagdad White female was mated 

 with an Istrian Yellow male from 9 :45 a.m. to 

 11 A.M. and then with a Bagdad White male 

 from 11 A.M. to 12 :15 P.M. (This was an exact 

 duplicate of the 1907 double mating just de- 

 scribed.) This mating produced (1908) 48 

 white cocoons and 20 yellow cocoons. Mating 



(1908) two of these white cocooners produced 



(1909) a small aU white lot, and a mating 

 (1909) of two from this lot produced (1910) 

 a smaller all white lot. Mating (1908) 

 another white pair from the Fj generation 

 produced an all white lot, and a mating 

 (1909) of two from this lot produced (1910) 

 a small aU white F^ lot. Mating (1908) two 

 yellow cocooners of the F^ lot produced 9 

 white cocoons and 12 yeUow cocoons. Mating 

 (1909) two of these F, white cocooners pro- 

 duced a small all white lot, while mating 



(1909) two of the yellow cocooners produced 



(1910) a very small all yellow lot. Another 

 mating (1908) of two yellow cocooners of the 

 original F^ lot produced 26 yellow cocoons and 

 one white cocoon and mating (1909) two of 

 these F, yellow cocooners produced (1910) 14 

 yellow cocoons and 2 white cocoons. Another 

 mating (1908) of two yellow cocooners from 

 the original F^ lot produced 28 yellow cocoons 

 and 12 white cocoons. Mating (1909) two of 

 these F, yellow cocooners produced 50 yellow 

 cocoons and no white ones, while mating 



(1909) two of the white cocooners produced 



(1910) 15 white cocoons and 1 yellow cocoon 

 (straggler?). Mating (1908) a yellow and a 

 white from the original F^ lot produced 

 (1910) 40 white cocoons and 16 yellow cocoons. 

 Mating (1909) two of these white cocooners 

 produced (1910) 28 white cocoons and 29 yellow 

 cocoons, while mating (1909) two of the F^ yel- 

 low cocooners produced (1910) 5 white cocoons 



