Figure 2S. — A putative 

 natural hybrid between 



Stansbury cliffrose is essentially self -incompatible. This characteristic was 

 determined by bagging branches of cliffrose which had flowers still in bud and also 

 branches on which all buds were emasculated. No pollen was added to the sacks. The 

 emasculated flowers produced no viable seed. The nonemasculated flowers produced only 

 10 viable seeds (1968-71) . Three of these were produced by a branch on which the paper 

 sack had been punctured, possibly allowing extraneous pollen to enter. The other seeds, 

 however, were produced on branches covered by intact sacks. These nonemasculated 

 control flowers bore 500 seeds, of which 10 germinated for a percentage of 2.0, compared 

 to 3.3 percent for Stansbury cliffrose crossed with Apache plume and 53.9 percent for 

 Stansbury cliffrose crossed with antelope bitterbrush (table 1). 



Figure 24. — A Stansbury cliffrose 

 flowerbud in proper stage of 

 d.et>elopment for emasculation. 



18 



