G. LAOMEDEA. 91 



distant from each other ; colour'yellow fawn ; height 

 about two decimetres. 

 Indian ocean. 



SIMPLE. 



3. Laomedea simplex. Stem simple ; cells long, 

 campanulated, and dispersed ; colour a deep brown ; 

 height two decimetres. 



On the fucus of Australasia. 



M. LAIR'S. 



4. Laomedea Lairii. Base or root branched ; 

 stem simple, or very slightly branching; cells dis- 

 persed, diverging, and supported on long peduncles ; 

 colour red-brown ; height a centimetre. 



Australasian seas. 



DICHOTOMOUS. 



5. Laomedea dkhotoma. Stem dichotomous, and 

 geniculated ; cells campanulated ; ovaria axillary, and 

 supported on curved peduncles. 



European seas. 



THORNY. 



6. Laomedea spinosa. Cells very small, almost 

 invisible; branches dichotomous, and terminated by 

 two bristly appendages; base composed of inter- 

 woven tubes. 



European seas. 



JOINTED. 



7. Laomedea genkulata. Stem geniculated and 

 uneven ; ovaria oval, truncated, and pedicelled ; pedi- 

 cle curved. 



European seas. 



