103 



GENERA 



BELONGING TO THE SECOND ORDER OF THE SECOND 



CLASS. 



Jania. Resembling moss, hairy and dichotomous ; 

 numerous ovaria. 



Corallina. Compressed and trichotomous. 



Cymopolia. Cylindrical and dichotomous; neck- 

 lace-formed. 



Amphiroa. Branches dispersed, dichotomous, tri- 

 chotomous, or verticillated ; articulations separated. 



Halimeda. With flat or compressed articulations, 

 generally fan-shaped. 



GENERA 



BELONGING TO THE THIRD ORDER OF THE SECOND CLASS . 



Udotea. Fan-shaped, marked with curved and 

 transverse lines. 



Melobesia. Chalky incrustation ; cells very small 

 and dispersed. 



