Belling: Inheritance in Plants 



355 



STINGING BRISTLES OF HYBRID 



Bristles from a ripe pod of the Velvet x China Fl hybrid, mounted in water. Most of them con- 

 tain air. Scale in tenths and hundredths of a millimeter. (Fig. 13.) 



Black plants were seen in several 

 families, but apparently none survived 

 to produce pods. Sixteen of these 36 

 plants had 15 or more survivors. Out 

 of these 16 families, 



(1) 3 were all stinging; 



(2) 9 were stinging and downy; 



(3) 3 were stinging and "Velvet"; 



(4) 1 was stinging, downy, and "Velvet." 



The calculated numbers are: 



(1) 1.8 families, constant stinging; 



(2) 3.6 families, 3 stinging to 1 downy; 



(3) 3.6 families, 3 stinging to 1 long tomen- 

 tum (mostly "Velvet," a few long black); 



(4) 7.1 families, 9 stinging to 3 downy to 1 

 "Velvet" to 3 black (or recessive downy). 



The elimination of the black plants 

 would cause a few of class (3) to appear 

 as class (1) ; and, together with the small 



size of the families, would cause most of 

 class (4) to appear as class (2). Hence 

 the numbers of different classes of 

 families of stinging parents point to a 

 segregation with two main factors. 



DOWNY PLANTS.— Out of 22 fam- 

 ilies, six were constant; and 16 segre- 

 gated into downy and smooth black. 

 Fourteen of these segregating families 

 were grown on poles. Their totals were : 

 Downy : Smooth Black. 



311 : 118 



(Calculated 322 : 107) 



From seven downy plants of one of 

 these F3 families, seven families were 

 raised in F4. One was constant, and 

 six segregated as follows: 



Downy. Smooth Black. 



157 : 57 



(Calculated 160.5 : 53.5) 



