WAVELENGTH (nm) 



Figure l.--Photosynthetical ly Useable Radiation of zooxanthel lae isolated from 

 Montastrea annularis , Discovery Bay, Jamaica. Relative whole cell absorbance 

 was measured at low temperature with a modified Cary 14 spectrophotometer. 

 Measurements of underwater spectral irradience were made with a prototype 

 spectroradiometer. Note that the algae from different depths vary with 

 respect to their absorbance of light energy and its spectral quality (see 

 Dustan, 1982, for experimental details). 



the absorption of light by both animals and plants. As such, the data will 

 overestimate actual primary production until the measure is more fully understood 

 and the model appropriately refined. 



191 



