vi COMENTS 



PAGE 



23. Chemical Nature <rf SoQs. IS 



2-L Air Cootoit 19 



25. Detaminatkm of Soil Properties 19 



KrprrimtaU 3. Porosity and Rate of Evaporation 20 



26. Laflnence <rf Precipitation upon Water Content 21 



27. Measoremait <rf R'tinfan. 21 



2S. PhTsiograjJiy 22 



29. The Inflooice of 9c^pe. 23 



30. The Infiooice of Surface 23 



31. The Inflnence erf CEmatic Factors 2-1 



32. Humidity 24 



33. Modifying iDfluence (rf Texoporatuie and Wind 25 



S4. Infiuence of Pressure and I^yaogra^hic Factors 26 



35. Effect <rf Climate and Habitat 27 



36. MeasoFement of Humidity 27 



37. SKmg and Cc^ PsyehrMneter 28 



3S. Making a Biding 29 



39. Use <rf Humidity Tables. 30 



Experimad 4. Measmng Humidity 30 



40. Method of Habitat Stufy 30 



41. Choice of Stations 31 



42. Omstant Factors. 31 



43. Smuhaneoos Readings 31 



44. Pmat and Hour Reading 33 



45. Records 33 



46. Kinds of Curves 34 



47. Combinatimis of Cmves 34 



4S. Plotting Curves 35 



49. Intervals Ua the Diffeieait Factors. 36 



Experiment 5. De*nnining the Physical Factors of Habitats. . 36 



CHAPTER III 

 ADJUSTSIEXT TO WATER 



50. RespcMiaes to Water StimulL 38 



Absorptiox 



51. General Rdations 38 



.52. The Form of Roots 39 



53. Primary Regicms of the Root 39 



54. Detailed Structure 40 



55. Orion and Structure of Root-hairs 42 



56. Effect of WatT Content upon Root-hairs and Roots 43 



Ezperiment 6. Structure of the Root and Formation of Root-hairs. 44 



xp"nni/ 7. Hydrotropasm. 44 



