EXPERIMENTS AND PRACTICAL WORK 49 



(b) Coco or caladium: There are a number of male and 

 female flowers without sepals or petals. 



(c) Corn: Staminate or pollen - bearing flowers are 

 borne on the tassel near the top of the plant, while the 

 pistillate flowers which change into the ear are separate 

 and are situated lower down. 



(d) Sunflower and other Compositce : In reality a number 

 of small flowers are borne together on a " head ". 



(e) Poinsettia: or "six months red and six months green": 

 A large, conspicuous, and brightly coloured floral bract 

 surrounds the true flowers. 



(/) Swan flower or Dutchman's pipe: Constructed so as 

 to attract flies and to keep them in captivity until ferti- 

 lization has taken place. 



(g) Orchids: Varied forms, having one of the three 

 petals more conspicuous than the other two. 



FLOWERS AND SEEDS (FERTILIZATION) 



I AND II 



(See Tropical Readers, Book II, pp. 56-62.) 



Expt. 64. Fertilization is due to Ripe Pollen coming" 

 in contact with Mature Stigma. 



(a) Pollinated Pistils develop Fruit. Examine the pistils 

 of a number of flowers that have been open for a day or 

 two, and record whether the stigmas are tipped with 

 pollen or not; observe which develop into fruits. 



(b) Flowers not Pollinated do not produce Fruit. Cover 

 over the female flowers on a pumpkin or cucumber vine 

 with a paper bag or with one of fine muslin before they 

 open; observe that fruit will not develop from those 

 flowers, as pollen cannot get at them. 



(c) Effect of removing Stamens. Carefully pull apart 

 the whorls of any bud bearing both stamens and pistils 



( C 282 ) 4 



