Agricultur, Horticultur, Forstbotanik. 367 



ohne es ganz zu erdrücken ; die Spitze wuchs weiter und zwar in die 

 Höhe dem Lichte entgegen. Alter der Tanne etwa 30 Jahre. 



Ferner werden zwei, je 40 Jahre alte Rotbuchen beschrieben, 

 die wie zwei Zwillingsbrüder nebeneinander jedes auf 2 Füssen 

 stehen. Das eine Exemplar ist 20 cm. stark und 8 m. hoch, das 

 andere 25 cm. stark und 10 m. hoch. Die Gabelung schliesst, vom 

 Boden ausgerechnet und senkrecht gemessen, bei 2, bezw. 2h m. 

 Höhe ab und vereinigt sich dann in je einen Stamm. Eine Ursache 

 für diese Zwieselung ist nicht bekannt; Zwieselungen nach oben 

 sind viel häufiger. Die Bäume werden abgebildet. 



Matouschek (Reichenberg). 



Olsson-Seffer, Pehr, Rubber planting in Mexico and Central 

 America. (The Agricultural Bulletin of the Straits and Federated 

 Malay States. Vol. VI. p. 1—33. January 1907.) 



The author Claims that the correct generic name of the Cen- 

 tral American rubber tree is Castüla, and not CastiUoa. The plant 

 was first described by Cervantes in 1794, and the name Castilla 

 is used in his description printed the same year. 



There are many different forms of Castilla elastica, Cerv. 

 Castilla markharniana is generally recognised as a distinct species, 

 and the Castilla cultivated in Ceylon is sometimes referred to as 

 this species. 



Castilla grows wild from 21° North latitude in Mexico, south- 

 ward through Guatemala, Honduras, San Salvador, Costa 

 Rica, Nicaragua, and Panama. In Central America it foUows 

 the Cordilleras on both sides, 'and in South America it grows 

 on the western slopes of the Andes, of Ecuador, and Peru. In 

 Central America there is plenty of land suitable for rubber plan- 

 ting, especially in Guatemala. The writer suggests that there 

 should be more Cooperation among the rubber planters in Mexico, 

 and Central America, and that experimental rubber culture should 

 be Started on a larger scale. 



Various Mexican plantations are named, and methods of culti- 

 vation carried out and some of these are described in detail, especially 

 in the case of La Zacualpa Rubber Plantation. Methods of planting, 

 selection of seeds, etc., are dealt with. The habit of wild Castilla is 

 described, one of the most noticeable features being that it prefers 

 small open spaces in the forest, and never selects a havy shade. 



The function of latex is discussed, and experiments made with 

 seedling Castilla plants described, one grown in an atmosphere 

 saturated with moisture produced a very thin latex, without anj^ 

 globules, whilst one grown under conditions favourable to excessive 

 transpiration had the ordinary latex of young seedlings, but rather 

 concentrated, the plant seeming to produce latex as a means of 

 protection. 



Tapping Operations are described, and the method of collection 

 of the latex. After thoroughh' washing, the rubber is pressed into 

 blocks in a strong screw press. It does not seem advisable to export 

 the rubber as "crepe" as it suffers considerably from oxidation. 



Sulphurizing the latex by a process corresponding to vulcaniza- 

 tion does not seem to have much to recommend it beyond its pre- 

 serving action on the crude rubber. In whatever way the sulphur 

 were added, the quantity must necessarily vary on different planta- 

 tions, and no uniformity could be achieved; also the method would 



