168 L. HILLIS-COLINVAUX 



9. Controlled environment room 



A walk-in controlled environment room, if available, permits a finer 

 control of both the temperature and lighting cycles, and some investi- 

 gation of environmental effects which are not possible if aquaria are 

 maintained in a multi-use room. Such a room, however, may restrict 

 sizes of aquaria and intensity of lighting. 



C. Some experiences with Halimeda culture 



Table XIII lists the species of Halimeda cultured, together with 

 other plants that have been introduced intentionally or inadvertently. 



Table XIII. Pahtial List of Organisms Maintained in Aquaria for Two 

 Months to Over One Year 



Using the approach described, sand-growing Halimedae have settled in 

 and grown well, with the iirst obvious growth of the transplants often 

 appearing in about five days (Section VI). On the few occasions that 

 some Rhipsalian Halimedae have been kept in seawater and not planted 

 immediately, rhizoidal growth has been noted on about the third day, 



