EXTENDED SERIES. 



67 



IX. Black, YBrBDP (Fig. 9). 



Hairs on ventral surface not so heavily pigmented as the dorsal hairs, and of a dull slaty- 

 black. Tail dark. Dorsal hairs deep, glossy black. Tuft of yellowish hairs at base of 

 ears. A few yellowish hairs scattered along the flanks, sides and feet. The hairs 

 around the anus are light yellowish. The feet are dark. 



Black X black. 



Ckoss 62. One or both of the parents homozygous. YiBriBiDiPi x YiBrzBiDiPi. Expec- 

 tation, all B. 



Cross 63. Both parents heterozygous in black. YiBriBDzPi x YiBviBDiPi. Expecta- 

 tion, 35, 1 Br. 



Cross 64. Both parents heterozygous in density. YiBriBiDdPi x YiBriBiDdPi. Expec- 

 tation, 3 B, 1 dB. 



Cross 65. Both parents heterozygous in dark eye. Y^BriBiDiPp x YiBrJBiDiPp. Expec- 

 tation, 3 B, 1 pB. 



Mating. 



Parents. 



B. 



492 

 168 

 189 

 114 

 131 

 135 

 379 



Unmarked X 2948 



455x919 



450x540 



Unmarked x 454 



543 X 444 



450x444 



Unmarked x unmarked . . . 



3 

 12 



6 

 12 



2 



7 

 60 



102 



1 

 1 

 2 

 1 

 1 

 4 

 20 



30 



