180 PLANT BIOLOGY 



7. Plant propagation. 



a. Seeds and their development into plants . . 6 lessons 



6. Conditions essential for the growth of plants . 2 lessons 



8. Plants in their relation to human welfare. 



a. Some uses of plants to man 3 lessons 



6. Forests and forest conservation 3 lessons 



9. Insects 15 lessons 



10. Birds 5 lessons 



11. Fish (and frog, if this form is taught) .... 14 lessons 



12. Single-celled animals 5 lessons 



13. The general structure of the human body . . 3 lessons 



14. Microorganisms and their relation to human wel- 



fare 10 lessons 



15. Nutrients and their uses 7 lessons 



16. Stimulants, narcotics, and poisons 10 lessons 



17. Digestion of the nutrients 7 lessons 



18. Circulation of the nutrients 6 lessons 



19. Respiration and the production of heat and 



power in man 7 lessons 



20. Additional topics in hygiene . 9 lessons 



