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alternate rows and virtually every one of them has the tendency to produce 

 either a rhizome branch or a new plant. The secondary and tertiary rhizome 

 branches which spring practically from every bud, if covered with soil, are 

 different in length. A few of them are equal to the primary branches and 

 continue these after the endbud has developed into an aerial stem, forming 

 sympodia and side-branches but the most part suspend their growth for 

 some time and form rows of tubers either on each side of the principal 

 secundary branch or, and this is more commonly the case, on the lower 

 side only. These abbreviated rhizome branches are called "sessile tubers" 

 by most authors and a complex formed by a rhizome-member with the 

 adhering branches is commonly called a palmate tuber, though the disposition 

 of the members is not at all what is called "palmate" in the botanical 

 terminology, but rather "pinnate." Rumph was the first to describe the 

 branching of a rhizome complex and compared the branches with their 

 side-branches to a closed first. The latter he called „toes" (traduced by 

 BuRMANN into articulationes or digiti). The primary bulb he called mother-root. 



The habit of the bulb and rhizome-complex are very characteristic 

 for any species and a most valuable help for the determination. Of no less 

 importance for this aim are the internal colour, the smell and the taste. 



The following colours where observed in different rhizomes. The ciphers 

 are taken from the "Code des couleurs" by Klincksick and Valette (1908) ; 

 (see above page 4). 



Orange-yellow to orange (151—126) C. domestica. 



C. xanthorhiza. 



Orange-yellow to pure yellow (156 — 161) C. purpurascens and allied 



species. 



Pale-sulfureus . (241—246) C. Zedoaria 



(206—216) C. Brog. 

 (226—236) C. Heyneana. 

 (236—241) C. Mangga. 



Pale ambercoloured (153 D) = C. Zedoaria old rhizome. 



Greenish blue 386 — C. aeruginosa. 



m 



Pale greenish blue 396 = „ and C. phaeocaulis. 



light-blue 442 = C. aeruginosa. 



Key to the determination of the principal species by 

 their subterraneous organs. 



A. Rhizomes very short or wanting; bulbs in groups together: 



a Short rhizomes consisting of few limbs, bent upward, and forming 

 new plants, with short broad branches, forked at the top, the whole forming 

 a short and compact rhizome-system. Internally very pale sulfurcous: 



C. petiolata. 



b. Rhizomes immediately upward bent and forming new plants;- no 

 branches: C. aurantiaca. 



