CONFERVA PUNCTALIS. 



C. filamentis fimplicibus lubricis tenuiffimis ; dinepimentis obfcuris, 

 articulis brcviufculis cylindricis, fuccus in globulos folitarios dcmum 

 congeflus. 



C. pun£hlis, Muller in Nova Acta, Pet. III. 



In Ditches and Pools not unfrequent. 



PERHAPS no Botanift examining this fpecies in its younger (late only would 

 allow it to be the C. punotalis of Muller, nor till it has arrived at its maturity, 

 when the green matter of the joints collapfes into a feries of globules ; then, 

 under any other than the higheft powers of the microfcope, the diflepiments by 

 their extreme thinnefs entirely elude the clofeft obfervation, and die plant accords 

 well with Muller's defcription, " filamentis inarticulatis, fimplicibus, ferie punfto- 

 fum longitudinali." 



C. pundtalis is frequently met with in Pools and Ditches, as well on Heaths as 

 in Marfhes. The colour of its filaments varies from a pale bright green to a 

 yellowifh green ; their length is from one to two inches ; but what will at once 

 diftinguifh this plant from all its congeners is their extreme tenuity, which is 

 fuch that when fmgle they can hardly be diftinguifhed by the naked eye : in this 

 refpecT: C. punclalis refembles C. muralis, but die different color, place and 

 mode of growth, and far different ftrudture when examined with a glafs, preclude 

 the poflibility of its being confounded with that fpecies. The diflepiments from 

 their tenuity are obfervable only when a ftrong magnifying power is applied ; 

 they divide the filaments into joints, whofe length is about equal to dieir thick- 

 nefs. Whilft the plant is young, thefe joints are nearly of a uniform greenifh 

 color, but with age the green matter of each joint collapfes into a globule, and 

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