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pollen but prevents it from falling to the bottom of the tube. 

 The pollen grains are spiny which causes them to adhere not 

 only to the insect but to the hairs on the style as well. The 

 slightly swollen anthers show spontaneous movements and 

 because of the shortening a mass of pollen is thrown out. 

 Tliis happens when an insect seeks the nectar which is secret- 

 ed by a ring surrounding the base of the tublar corolla, as it 

 is In all other Compositae. In the later stage the pistil has 

 protruded showing the stigma. If the pollen has not been 

 carried away by the insect self-pollination may occur. 



Bull thistle, flowers with us from the latter part of July 

 to September and is visited by many worker bumble bees. 

 Mr. Weed says: ''But they are not the large and handsome 

 bees found on the Arbutus in May, they are much smaller in 

 size and less attractive in appearance. The large specimens 

 which appear in spring are the hibernating females or 

 queens. In addition to bees many Diptera occ ir, especially 

 syrphus flies, Lepidoptera- The Colias philodice &b "w^W 

 as Pieris, Danais archippm and Papilio turnus visit the 

 thistle flowers. 



Our native Gnicug lanceolatus, var. discolor is equally 

 interesting. 



Dandelion. In Taraxacum officinale the numerous 

 flowers are collected in a head. All of the flowers of the 

 head are alike and bright yellow. The head is open in 

 bright sunlight of the early morning and partially closed 

 about noon. When fertilized the "flower stem" contracts, 

 ripens its "seed", and elongates when ripe, so that the 

 "seed" may be distributed. An abundance of nectar is pro- 

 duced which rises up for a considerable distance in the tube, 

 making it accessible to many insect visitors with short tongues. 

 The honey bee is a very common visitor as are also species 



