22 



5. How long^ before movement takes, place ? Use a lens. 



6. Does relaxation of the movement occur while tke object remains 

 on the tentacle ? 



7. Do all the objects mentioned secure equal reactions ? 



8. How is the amount of secretion influenced by the different ob- 

 jects ? 



9. Place a small cube of 1 mm side, with sharply cut edg-es, of the 

 white of a hard boiled egg on each of several sundew leaves, and deter- 

 mine if the albumen is digested after a day or two. 



10. Determine the structure of a tentacle, using- a microscope. Ob- 

 serve the spirally thickened wood-fibres, or "water-pipes." 



11. Try the action of very dilute solutions of ammonium salts on the 

 bending of the tentacles. 



12. Try the .action of sugar, starch, dilute alcohol, milk, mucous, and 

 saliva. 



13. Are the stalks of the tentacles sensitive ? 



14. Repeat Francis Darwin's experiments as to the effect of feeding 

 sundew with roast meat (1-50 grain) on the nutrition and reproduction 

 of the plant. 



XXXV. The Wheat Rust. 



1. Collect specimens of diseased barberry leaves, and determ'ne 

 when the cluster-cups are mature. 



2. Make careful drawings of the cluster-cup. 



3. From the mature cluster-cup remove some spores to a moistened 

 leaf seedling of wheat or oat plants. 



4. Determine when the rust appears on the wheat or oat leaves after 

 inoculation. 



5. Inoculate other wheat plants and other oat plants from the first 

 inoculated plants. 



6. Try to get specimens of wheat or oats infested with Black Rust, 

 and which have wintered over in exposed places. Determine how the 

 Black Rust spores germinate. 



XXXVI. The Life History of the Toad or Frog. 



1. Collect the eggs at the river in early spring. About how many 

 eggs are laid by one toad ? What is the difference between the toad's 

 eggs and the frog's eggs ? Keep the eggs in a flat glass dish in water 

 and watch them hatch. Change the water every two or three days. 

 Draw a few eggs. 



2. Draw the tadpole in its various stages of development. Note 

 some of the habits of the tadpole, how it swims, breathes, etc. 



