CONFERVA ATRO-PURPUREA. 



C. filamentis fimplicibus, anate hie illic inaequaliter torofis, atro-pur- 

 pureis ; articulis diametro dimidio brevioribus, fmgulis feriem du- 

 pliciem globulorum includentibus. 



C. atro-purpurea. Roth, Cat. Bot. III. p. 208. t. 6. 



Bantry Bay, Ireland. Mifs Hut chins. 



C. atro-purpurea was firft difcovered growing upon mill-wheels, in the vicinity 

 of Bremen, and communicated to Dr. Roth by Profeflbr Mertens. Mifs 

 Hutchins has lately gathered it in Bantry Bay, and from her, through the 

 medium of our mutual friend, Mr. Turner, I have received fpecimens of this, 

 as well as of feveral other fpecies at prefent undefcribed ; an account of which 

 I ihould have been happy to publifh, had they not fuffered too much change in 

 drying. The prefent is one of the few Confervse that may be reftored by 

 immerfion in water, and I have therefore ventured to make the annexed draw- 

 ing from a dried fpecimen. 



The root is fibrous ; the filaments grow in fmall tufts, they are about two or 

 three inches in length, thinner than human hair, nearly ftraight, of a glofTy 

 hue, and dark purple color. As in C. fufco purpurea, when the plant is young 

 the filaments are mod probably of an uniform thicknefs, and they are fo de- 

 fcribed by Dr. Roth, but thofe now before me are in fome parts fwelled, and 

 much thicker than in others ; the difTepiments are narrow and pellucid ; the 

 joints are in length but about half equal to their diameter, and each contains 

 two rows of granules difpofed tranfverfely, which, like thofe of C. bipunctata, 

 occasionally take a (lellated appearance. A longitudinal pellucid line is obfervable 

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