19 



P. tenuissima, Grev. ; New York Bav. 

 P. latifolia, Grev ; Long Island ^und. 

 V . platiginea y Koih ; Stoningion. 



Vf. Asperococcus. Lamour. 



Frond unbranched, tubular, rarely compressed. Fruit scattered 

 over the whole surface. 



A. situosus ; Massachusetts. 



A claratus ; Florida. 



A. echinatus, Mertens ; Florida. 



VII. Dictyospii^eria. 

 D. favulosa Decarsne ; Key West. 

 1 Sjj. ? or new ; Florida. 



VII T. Halodictyon. 

 1 Sp ? or new ; Key West. 



9. Litosiphon. Harvey. 

 L. Laminar ice, Lyngb. 



Order V.—CHORDARlACEiE. 



Frond cylindrical, branching. Spores enclosed within the sub- 

 stance. Contains fuur genera, namely — 



I. Chordaria, Agardh — Same, a. cord. 



II. Mesoorloia, A<j. — Name, vicid centre. 



III. Leathesia, Gray — Name, Rev. G R. Leathes. 



IV. Elachistea, Fries. — Name, The least. 



I. Chordaria. Ag. 



Axis cartilaginous and dense. Filaments branched. 

 C. divaricata, Agardh ; New York Bay. 

 C. flag eliij ormis, Mull ; hong Island Sound. 

 3 Sp. ? or new ; N. Y. Bay and L. I. Sound. 



II. Mesogloia. Ag. 



Frond filaform, gelatinous, much branched. Spores attached to 

 the ramuli. 



M. virescens, Carmichael ; Key West. 



M. affinis, Berkely ; Key West. 



M zostericola ; Florida. 



M. Griffiths iana, Greville ; L I. Sound. 



M. vermiculosa, Ag. ; L. I. Sound. 



M. multifida ; Green port. 



III. Leathesia. Gray. 

 Frond globose or shapeless. 

 L. marina, Ag. ; L. I. Sound. 



