HORACES 263 



Pollination, Fertilization, and Development of the 

 Hops." — The long, brush-hke stigmas adapt the plant 

 to wind pollination. When the pistillate inflorescences 

 are young, the stigmas protrude from -between the small 

 "bracts" and become very conspicuous. Only the basal 

 bracts of the inflorescence are to be seen. As soon as 

 fertilization has taken place the stigmas ("brush") drop 

 off and the "bracts" rapidly increase in size. 



The necessity for fertilization to secure the best develop- 

 ment of the "hop" has been determined by a number of 

 observers. The hops will only develop properly when 

 a certain number of bracteoles bear seeds. If the young 

 pistillate inflorescences ("burrs") are enclosed in paper bags 

 to prevent fertilization, no seeds result, and the hops are 

 poorly developed. It is true that the bracteoles develop 

 to some extent without fertilization of the ovules, but the 

 bracteoles connected with normal seeds are much larger and 

 a brighter yellow than those bearing rudimentary seeds. 

 Furthermore, hops, not fertilized, remain in blossom longer 

 than those fertilized. Howard has shown that hops arti- 

 ficially polHnated start to grow out at once, while those not 

 pollinated at all begin their growth seven to ten days later. 

 He shows that fertilization stimulates growth, hastens 

 ripening, improves the color and increases the mold-resisting 

 power of the plant. Salmon and Amos have shown that, in 

 England at least, seeded hops bearing an average of 9.5 

 seeds per hop, contained 15 per cent, resin and produced 

 147 pounds of resin per acre, while seedless hops contained 

 17.2 per cent, of resin and produced 92 pounds of resin 

 per acre. It is true that there are certain disadvantages 

 connected with growing seeded hops. Extra space is needed 

 for growing staminate plants, and there is also a possi- 



