CONFERVA TETRAGONA. 



C. filamentis ramofrffimis ramulis fafciculatis brevibus fimpliciufculis ; 

 articulis ovato-cylindraceis, capfulis feflilibus fub globofis. 



C. tetragon a. With. V. p. 405. 



In the Sea, parafitical on the Fuci. At the Bill of Portland, Col. Velley. In 

 Cafwell and Llanglan Bays, near Swanfea. Shore at Weymouth, D. Turner. 



THIS elegant Conferva was difcovered by Col. Velley and Mr. Stackhoufe at 

 the Bill of Portland, and by them communicated to Dr. Withering, who firft 

 publifhed a defcription of it in an Appendix to the third edition of his arrange- 

 ment of Britifh plants. 



C. tetragona is a fpecies by no means found either generally or in abundance ; 

 it grows parafitically on the larger Fuci in fhrubby tufts, of a light purplilh red 

 color, feldom exceeding two inches in length. The root is a callus, common to 

 many ftraight and undivided Items, befet with branches, not difpofed as in C. 

 plumula on two oppofite fides only, but proceeding indifcriminately from every 

 part of it ; nearefl; the root Ihort, thence gradually increafing in length to the 

 center, and again decreafing towards the fummit, fo that the general outline is 

 irregularly ovate ; they are again divided nearly in a fimilar manner and are 

 befet with numerous cluftered fpine-like ramuli, extremely Ihort and for the 

 moft part fimple, compofed of joints fomewhat refembling thofe of Fucus 

 articulatus, the ultimate one terminated by an acute point. The fructification 

 confifts of fmall globular feffile capfules arranged on the upper fide of the 

 armuli. 



