LIST AND CONTENTS OF BUTXETINS 1 TO 100. 23 



of the fruit when picked; how to obtain more imil'onn and better colored 

 fruit; influence of delaying- the stora^'P of the fruit; influence of storage tem- 

 perature; influence of a fruit wra])per; influence of ' cultural conditions; 

 influence of the type of package — The behavior of the fruit when removed from 

 storage — The importance of good fruit — A]iple s-cald : Xature of the scald ; 

 influence of maturity of the frint on scald; influence of tem])crature on 

 scald ; the temperature in which tlr.' fruit is removed from the storage house; 

 influence on scald of delaying the storage of the fruit after it is picked; 

 influence of a fruit wrapper on scald ; varieties most susceiitible to scald ; 

 treatment to prevent scald — Comparison of varieties in cold storage* — Outline 

 of cultural conditions — Variety catalogue — Snniniarj- — Descrii)tion of plates. 



* No. 49. The Culture of the Central American Rubber Tree. By 



O. F. Cook, Botanist in Charge of Investigations in 



Tropical Agriculture. 1903. 8G pj)., 18 pis. Price, 25 



cents. 



Contents : Introduction- — The status of Castilla rubber culture : Castilla 

 versus Ilevea ; uncertainties attending rubber culture; extent of the Castilla 

 rubber industry; Castilla in the West Indies; Castilla culture for Porto Rico; 

 rubber in the Philippines— llotanical study of Castilla: Difficulties in studying 

 tropical trees; the original description of Castilla; description and botanical 

 characters; species and varieties of Castilla; Hooker's monograph of Castilla; 

 Costa Hican species of Castilla; field notes on Castilla in Guatemala and 

 southern Mexico ; habits of Castilla in the wild state ; the rubber tree and the 

 trumj^t t tree ; Castilla not a genuine forest tree — Imju-ovement of rubber trees 

 by selection — Problems presented by the latex, or "milk": Evolutionary argu- 

 ments regarding latex; functions ascribed to latex; the structure of latex; 

 seasonal influences on latex ; latex in desert jjlants ; water storing as a func- 

 tion of latex ; significance of multiple tajiping — Climate and rubber produc- 

 tion : A continuously humid climate not necessary for Castilla; greater 

 abundance of Castilla on the drier Pacific slope ; freer flow of milk in drier 

 regions; decrease of milk with altitude and continuous humidity; Castilla in 

 Nicaragua ; Castilla in Costa Rica ; Castilla on the Isthmus of Panama ; anal- 

 ogy of the Assam rubber tree ; the Para rubber tree in humid localities ; pro- 

 ductiveness of Para rubber trees in dry situations ; the true climate of Hevea— 

 The culture of Castilla : Shade in the culture of Castilla ; shade not a neces- 

 sity ; relative cost of shade culture ; effect of shade on form of tree ; shade 

 and rubber production ; leguminous shade trees to be preferred ; distance 

 between trees ; methods of clearing land for rubber planting ; clean culture 

 with forest protection ; methods of handling Castilla seeds ; seed beds and 

 nurseries ; propagation of Castilla from cuttings ; Castilla as a shade tree — 

 Extraction of the latex of Castilla: Primitive methods of tapping; age at 

 which planted frees may be tapped ; direction and shape of incisions ; tapping 

 instruments; multiple tapping; protection against thieves — Methods of coagu- 

 lating the latex of Castilla : Coagulation by creaming ; discoloration of Cas- 

 tilla latex ; other methods of coagulation ; coagulation of scrap rubber — 

 Productiveness of Castilla : Yield of wild trees ; yield of cultivated trees — ■ 

 Profits and prospects of Castilla culture: Management of rubber plantations.; 

 security of investments in rubber plantations; requirements for successful 

 rubberplantations ; opinion of the United States consul-general in Mexico — 

 Concluding summary — Description of plates. 



* No. 50. Wild Rice : Its Uses and Propagation. By Edgar Brown, 



Botanist in Charge of Seed Laboratory, and Carl S. Sco- 

 field, Botanist in Charge of Grain Grade Investigations. 

 1903. 24 pp., T pis. Price, 10 cents. 



Contents : Introduction — Distribution and habitat of the plant — Life his- 

 tory and natural propagation — Botanical description: General morphology; 

 the' root; the stem ; the leaves ; the panicle — Varieties — Diseases — Harvesting 

 the seed — Preparation of the seed for food purposes — The food value of wild 

 rice — Artificial propagation — Previous failures in planting — Plantings made in 

 1902 — Storing seed — Suggestions for harvesting, storing, and planting — De- 

 scription of plates. 

 101 



