PAGE 



\III. Mctliods of {l(>t(Htinn the presence of rubber and deter- 



iiuninn its amount '•^1^^ 



a. Microscopical nu'thods '-^10 



b. Chemical analysis 216 



IX. Hcsultsof tlic chemical analyses and microscopical examina- 

 tions; talmlation of percentage of rubber in each variety 226 



X. Distribution of rubtuT in the plant 234 



(;. Hcfiional distribution in the ])lant 234 



6. iSiM'cific distribution in mature tissues 239 



XI. Factors influencing rubber content 243 



a. Variation with the botanical variety. 243 



b. Variation due to environment 24.'5 



c. .Sea.sonal variation 246 



Xll. Methods of harvesting: season, age, depth of cutting, etc... 248 



XIII. Possibilities of Chrysothamnus as a cultivated plant 2.51 



XIV. Cultural requirements 2.5.5 



XV. Summary 2.57 



8. The Occurrence of Rubber in Certain West American Shrubs, by 



Harvey Monroe Hall and Thomas Harper Ctoodsjjeed 265-278 



I. Chrysothamnus (exclusive of C. iiauseonu.s) and Haplopappus 265 



II. Regional distribution of rubber in Haplopappus 274 



III. Species in which no rubber is found 276 



No. 9. Phycological Contributions. I, by William Albert Setchell and 



5jathaniel Lyon ( Jardner ' 279-324 



Xo. 10. Plantac Mexicanae Purpusianae. X, bv Townshcnd Stith Bran- 



degee ' 325-.331 



Xo. 11. Phycological Contributions. II to VI, by William Albert Setchell and 



Nathaniel Lyon Gardner 333-426 



II. New Species of Mj'rionema 334 



III. New Species of Compsonema 353 



IV. New Species of Hecatonema 377 



V. New Species of Pylaiella and Streblonema 385 



VI. New Species of Ectocarpus 403 



No. 12. Notes on Pacific Coast Algae, by Carl Skottsberg 427-436 



1 1 . On t h(> Calif ornian "Delesseria quercifnlin " 427 



No. 13. Undescribcd Plants Mostly from Baja California, by Ivan Murray 



Johnston 437-446 



No. 14. The Morphology, Development, and Economic Aspects of Schizo- 



phyllum commune Fries, by Frederick Monroe Essig 447-498 



I. Introduction '. 448 



II. Material and Technique 449 



III. Morphology 451 



1. General characteristics of the sporophores 451 



2. Description of the mature sporophore 4.53 



3. Microscopic structure 454 



IV. Growth of the sporophore 458 



1. Development in general 458 



2. Origin and development of the "gills" 461 



3. Taxonomic interpretation of the structure and devel- 



opment of the sporophores 463 



V. Economic aspects 464 



1. Geographical distribution 464 



2. List of host plants 46.5 



3. Extreme hardiness of the fungus 4()() 



4. Relation of the mycehum to cells of dead wood 467 



5. Growths upon fresh wood and living trees 46<S 



6. Methods of infection under natural conditions 470 



7. Association with other wood decay fungi 471 



VI. Summary and conclusion 472 



VII. Acknowledgments 473 



Literature cited 473 



Explanation of plates 478 



Index 499 



[ii] 



