ALGiE. 171 



Frond 4 inches or more in length, irregularly divided; the branches 

 alternate or opposite, 3 or 4 inches long, much attenuated to the apex, 

 and either simple or once, rarely twice, forked; either destitute of 

 ramuli, or with a few lateral ones. All the frond is, as it were, hairy 

 with short pile, this being the tips of the filaments of the periphery 

 protruding through the lime-covered frond. These filaments are 

 remarkably robust in this species. 



Halimeda Tuna, Lamour. ? Feejee Islands. 



The lower part of our specimen is wanting, but the upper part 

 agrees perfectly with Ellis and Solander's figure of H. Tana. 



Caulerpa clavifera, Ag. Tongatabu and Feejee Islands. 



Caulerpa clavifera, var. lamourouxii. Tongatabu. 



Caulerpa Freycinetii, Ag. Wilson's Island and Tongatabu. 



Caulerpa mamillosa, Mont Rosa and Wake Islands. 



Caulerpa plumaris, Ag. Tongatabu and Feejee Islands. 



Caulerpa falcifolia, Harv. & Bail. (Tab. 8, fig. 4, 5.) 



G. caule repente glabro, ramis erectis simplicibus vel furcatis foliosis ; 

 follis densissimis widique insertis imbricatis falcalis compressis mucro- 

 natis. 



Hab. Tongatabu. [Also Lifuka and Vavau. — W. H. H.] 



Stem slender, glabrous. Branches erect, 2 or 3 inches high, densely 

 clothed with closely set imbricated leaves, inserted on all sides. 

 Leaves nearly 2 lines long, compressed, falcate, mucronate. 



Caulerpa Pickeringii, Harv. & Bail. (Tab. 8, fig. 1-3.) 



G. caule prostrato spongioso foliis demissime vestito per totam longitu- 

 dinem radicante, ramis erectis brevibus mamillwformibus spongiosis 

 foliosis ; foliis verticillatis creberrimis horizontalibus plaries dichotomis, 

 segmentis fastigiatis apicibusque furcatis vel bimucronatis. 



Hab. Wilson's Island, Paumotu Group. 



Fronds prostrate, rooting along the whole under side, branched, and 

 densely leafy, several inches long, a quarter of an inch in diameter, 



