CONTENTS 



PART I --ANATOMY 



PAGE 



INTRODUCTION 3 



CHAPTER 



I. General Directions for the Preparation of Material and the Value 



of Particular Sections 16 



II. The Growth Ring : its structural features and relation to age ... 24 



III. Tracheids : spiral, pitted, and resinous wood tracheids, their structure 



and relation to development 33 



IV. Bordered Pits : their genesis, structural variations, distribution, and 



phylogenetic relations 59 



V. Medullary Rays : their morphology and kinds 78 



VI. Medullary Rays (continued']: ray tracheids, their morphology and 



distribution 88 



VII. Medullary Rays (continued) : relations to development 103 



VIII. Wood Parenchyma : crystallogenous idioblasts and resin cells, their 



structure and relations to classification 109 



IX. Resin Passages: their morphology 123 



X. Resin Passages (continued} : their distribution and relations to phy- 



logeny, and classification 138 



XL General Phylogeny : based upon the data of the preceding chapters . 154 

 XII. Durability of Woods and their Preservation as Fossils : a discussion 

 of the principles involved in the durability of woods, and the princi- 

 pal ways in which they are preserved in a fossil state 162 



XIII. Decay : Its Mode of Action and Effects : a discussion of the chief 

 factors concerned in promoting decay, the way in which it operates, 

 and the principles underlying treatment for its arrest 175 



PART II SYSTEMATIC 



Synopsis of Genera for the Cordaitales, Gingkoales, and Coniferales . . . 195 



Cordaitales 198 



Cordaites 198 



Dammara 203 



Araucaria 203 



Gingkoales 209 



Gingko 209 



vii 



