Belling: Inheritance in Plant Hairs 



353 



TOMENTUM OF VELVET BEAN 



The fresh tomentum from a nearly full-grown pod of Velvet bean. Only a few of the hairs have 

 become twisted. Mounted in water; scale in tenths and hundredths of a millimeter. (Fig. 1 1.) 



(6) long tomentum, usually softer and 

 blacker than No. 5, but accompanied 

 with black tomentum over the whole of 

 the plant; 



(7) short tomentum, less than half 

 a millimeter, accompanied by black 

 tomentum over the whole plant and 

 serious floral abnormalities. 



(In the Velvet- Yokohama cross there 

 were no fine downy pods.) 



Some of the stinging plants had 

 stouter bristles, some had stripes of red 

 bristles on their pods like the wild 5. 



pruritum, some had more erect bristles, 

 and a few had sparse bristles. The 

 color varied from yellow to gray, usually 

 with a patch of red bristles at the base 

 of the pod. Some few stung more 

 severely than the first-generation 

 hybrids. 



Among the downy plants, the fine 

 downy were greatly in the majority 

 (except in the Velvet- Yokohama cross), 

 but they graded into the coarse downy. 

 Measurements of the hairs of nearly 

 300 plants under the microscope showed 



