8 ILLUSTRATIONS. 



Page. 

 Fig . 8 . Diagram showing the root system of a typical dry-land olive tree on the 

 Pope olive plantation, showing the position and distribution of the 



roots in the soil 29 



9. Diagram showing the annual rainfall at Los Angeles, Cal., as presented 



in Table VI - ----- 31 



10. Diagram showing the monthly means and summation of heat units of 



places in the olive-growing regions, illustrating the seasonal activ- 

 ity and heat requirements of the olive, arranged from Table IX 40 



11. Transverse section of a young lateral root of the third order of an olive 



tree from Palm Springs, Cal., showing a very hairy epidermis and 

 cortex '* ' 



12. Inner portion of the same transverse section of the olive root shown in 



figure 11 "^^ 



13. Transverse section of a lateral root of the first or second order of an 



olive tree, showing the development of phellogen and cork 48 



14. The same transverse section shown in figure 13 of the root of an olive 



tree, showing the development of a secondary cortex and paren- 

 chyma rays from the cambial strata 48 



15. Diagram of the root of an olive tree, showing the general arrangement 



of tissues described in figures 11 to 14, inclusive 48 



16. One of the peltate hairs from the surface of an olive leaf - - 50 



17. A sunken stoma and the uneven dorsal surface of an olive leaf 50 



18. Ventral face of an olive leaf, showing the thickened walls of epidermal 



cells and palisade cells 51 



19. Pneumatic tissue of the dorsal side of a blade traversed by stereome 



cells ^1 



20. Development of cork layers in the cortex of an olive stem 52 



192 



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