91 



Cyperaceae. 



4. Cypcrus pennatus Lmk. (In P e n z i g ' s paper wrongly named 



C. digitatus Roxb.). 



5. Fimbristylis spat/iacea Roth. (See p. 90). 



These two species are reproduced by seeds only. 



Casuarinaceae. 



6. Casuarina equisetifolia Fiet. L. 



Fast growing tree of level or gently sloping, well-per- 

 vious beaches rich in lime and lacking in humus and similar 

 localities close back of these. Kamerling ') found tu- 

 bercles on its roots, which he thinks may be inhabited by 

 nitrogen-fixing bacteria in the same way as those of 

 many Leguminosae. In |ava this tree has been found only 

 in a few localities (i.a. on the beach of Tji Lintjing, east 

 of Tandjong Priok, which is very rich of shells), but on 

 several coral-islands in the Java-sea it is rather numerous. 

 The fruits, which burst when ripe and then easily let escape 

 the winged seeds, can remain floating on sea-water for a 

 few days; the seeds themselves possess also floating-power -). 

 Over land the seeds may be spread by wind, across the sea 

 by sea-currents. When the tree has attained a certain age it 

 emits from its roots many young shoots which often form a 

 small grove around an old trunk. If, by some cause or other, 

 the substratum grows too rich of humus, Casuarina, when not 

 protected by man, gets gradually superseded by other trees '). 



Lauraceae. 



7. Cassytha filiformis L. 



Twining or partly decumbent, much branched, green or 

 brownish-orange, polyphagous, long-lived parasite r '\ often 



M Z. Kamerling, Over het voorkomen van wortelknolletjes bij Casuarina equiscti- 

 folia in Natuurkundig Tijdschrift Ned-Indie LXXI (19H), p. 20. 



'-) On the Keeling-islands u p p y found the seeds in the drift-zone. 



3 ) Such is, locally at least, since some years happening on the islands of the 

 Krakatao-group. Docters van Leeuwen'') states that in 1921 on Verlaten 

 Eiland the old forest of Casudrina equisetifolia L. in which the trees grew wide 

 apart and gradually perished, was in course of being replaced by a mixed forest and 

 that the Casuarina-forest on Krakatao ,,\vas in several places mostly already fairly old 

 ,,with few rejuvenated parts". 



') A specimen in the Buitenzorg Botanical Gardens had in 1924 reached an age 

 of upwards of 20 years. 



5 ) W. Docters van Leeuwen, I he Vegetation of the Island of Sebesy, 

 situated in the Sunda-Strait, near the Islands of the Krakatau-group; in the year 1921, 

 in Ann. |ard. Bot. Buitenzorg XXXII (192:5), pp . 158, 159, 160. 



