274 BRITISH SEA-WEEDS. 



loosely interwoven masses ; cells nearly twice the length of 

 their diameter, dividing transversely in the middle at ma- 

 turity. 



This species was also formerly a Conferva. It grows 

 in ditches and pools, which are rendered more or less 

 brackish by the influx of sea-water. It is of a dark- 

 green colour, and rigid texture, and does not adhere to 

 paper when dry. 



Chaetomorpha linum. The twine Chsstomorplia. 



Threads robust, from a few inches to several feet long, 

 curled, rigid, growing, unattached and floating, in loosely 

 interwoven layers of considerable extent ; cells about the 

 length of their diameter, dividing transversely at ma- 

 turity. 



This species varies much in colour, from pale to dark- 

 green, and is sometimes variegated. It is of a rigid 

 brittle texture, and does not adhere to paper when dry. 

 It grows in large quantities in tidal ditches. This, too, 

 was a Conferva. 



Chaetomorpha tortuosa. The tortuous Chaeto- 

 morpha. 



Threads slender, tortuous, rigid, curled, growing in closely 

 interwoven layers, which spread over and adhere to pro- 

 jections of rock, and other substances with which they may 

 come in contact ; cells varying in length, usually about 

 twice that of their diameter. 



This plant grows on rocks, etc., in tide-pools, and is 

 not uncommon. It was formerly a Conferva. 



