CONTENTS xi 



CHAPTER X 



The Ceara Rubber Tree {3Ianihot Glaziovii, Miill. Arg.) 



Species of Manihot — Manihot Olaziovii — Botanical characters — 

 Distribution — Collection of the rubber in Brazil — Cultivation — 

 -Y- Climatic conditions and soil — Formation of plantations — Rate of 

 growth — Tapping — Coagulation of latex — Yield of rubber — Com- 

 position of Ceara rubber — New rubber-yielding species of Manihot 



pp. 137-159 



CHAPTER XI 



The African Rubber Tree {Funtumia elastica, Stapf.) 



Kickxia and Fimtumia — Funtumia elastica — Botanical characters — 

 Distribution — Climatic conditioiis — Soil — Native methods of tapping — 

 Native methods of preparing the rubber — Cultivation — Formation of 

 plantations — Diseases and pests — Rate of growth — Plantation tapping 

 methods — Coagulation of latex — Yield of rubber — Composition of 

 Fivntiimia rubber .... ... pp. 160-185 



CHAPTER XII 



The African Rubber Vines 



African rubber vines — Plants yielding root-rubber — Botanical 

 characters — Growth of rubber vines — Collection of the rubber — 

 Yield of rubber from vines — Yield of rubber from rhizomes (root- 

 rubber) — Cost of collection — Improved methods of exploiting rubber 

 vines — Cultivation of the vines — Composition of vine rubbers 



pp. 186-211 



CHAPTER XIII 



The Central American Rubber Tree {Gastilloa elastica, 



Cerv.) 



Species of Castilloa — Castilloa elastica — Botanical characters — 

 Distribution — Native methods of collecting the rubber — Cultivation — 

 Tapping of cultivated trees — Preparation of the rubber — Yield of 

 rubber — Composition of Castilloa rubber . . . pp. 212-226 



