134 



The Plant World, 



which the niajority of heads began blooming on the same date 

 (plants 1744.01, 1746.01 and 1777.01). The end of bloom of 

 plant 1744.01 niav have been delayed one day by the unfavorable 

 climatic conditions of Jnly 17 though it cannot l)e said with 

 certainitv that all tlie llowers which remained unopened on the 

 17th would have opened on that da\- if conditions had been 

 favorable. Unrecorded observations of previous vears show- 

 that several da\s of unfavorable weatlier materialh' lengthen 

 the bl( oniing ] eri d. 



ViR. 2. — DilTerciit 'tagcs in the b'.oo-.ninjr of liiiuithy bead?. <:•) Beginning of bloom. 

 (!)) I'liU b'.ooni: (cl ICi.d of lilooni 



The time of dav at which Ijloomings occur is just l^efore 

 davbrcak. As a rule the greater part of the flowers which are to 

 bloom on a given day v ill be open by three o'clock in the morn- 

 ing, especiall\ if the night has been warm. A few straggling 

 flowers, i)articidarlv those on heads or j^arls of heads which are 

 blooiuing for the first time mav be delated for an hour or ]X)Ssi- 

 l)lv two lioms but tlie great mass come into bloom at a])i:)roxi- 

 nialclv the same lime. Contrarv to general o]hnion the entire 

 head does not come into bk)om at the same time. If the i)lant 

 is just beginning to bloom, or if weather conditions are not 



