OLIVE COLORED ALG^. 121 



Sub-order — PUNCTARIEM. 

 QkQx\\x%.— PUNCTARIA* Grev. 



PUNCTARIA LATIFOLIA,t GrEV. 



Fronds, pale olive green ; thickish, membraneous, 

 soft and tender, more or less dotted with minute 

 spore masses, suddenly tapering at the bottom, from 

 one to three inches wide in the broadest point, and 

 from eight to twelve inches long, the proportions 

 the same in the smaller plants. When young, the 

 substance is thin and soft, and almost gelatinous to 

 the touch, being then covered with very short pel- 

 lucid, almost invisible hairs. In that state it is of 

 a light olive green color. When older, it gets 

 darker. The margin of the frond wavy, and in old 

 plants the substance of the frond is thicker and 

 more rigid. In that condition it will be distin- 

 guished from plants of the next species chiefly by 

 its sudden narrowing at the base. 



It is a summer annual, growing between tides on 

 stones -and Algae. It will be met with most com- 

 monly in the var. Zosterce, or P. tenuissima, of Har- 

 vey's " Nereis," a small form, not more than two or 



* Punctaria = Dotted, 

 t Latifolia = Wide-leaf. 



