y. CERAMIACE^. 227 



articulations four to eight or twelve times as long as broad. Kiitz. Sp. Alg. p. 662. 

 J. Ag. Sp. Alg. 2, p. 90. Griffithsia equisetifolia, Ag. — Harv. Phyc. Brit. t. 67. 

 Conferva equisetifolia, E. Bot. t. 1479- Dillw. t. 54. 



Hab. (A specimen sent to me by Mr. Hooper, of Brooklyn, without locality 

 marked ; W. H. H.) 



Stems six or eight inches long, robust, much and very irregularly branched ; 

 the branches alternate or fascicled, undivided, but set with one or more series of 

 lateral branches. All the parts of the frond are clothed with ramelli. On the 

 older parts of the stem and branches these form an irregular shaggy coating ; but 

 on the younger portions they are regularly whorled at the nodes, once or twice or 

 many times forked, imbricated, mth the apices generally incurved. The articula- 

 tions vary much in length in different specimens. Colour, when recent, a fine dark, 

 crimson-lake. Substance firm. It gives out a carmine tint when plunged for a 

 short time in fresh water. 



I regret that I cannot say from what part of the Amei'ican Coast Mr. Hooper 

 procured this plant, of which I have as yet seen but a small fragment ; but it is 

 sufficient for identification. 



VII. GRIFFITHSIA. Ag. 



Frond filiform, dichotomous, articulated, monosiphonous, naked. Favellce gene- 

 rally several in a cluster, subtended by a regular involucre formed of numerous 

 incurved ramelli, sessile or pedunculate, containing, mthin a gelatinous periderm, 

 numerous angular spores. 2'etrasj?ores contained within an involucre formed of 

 incurved ramelli, spherical, attached to the inner faces of the ramelli, at length tri- 

 angularly parted. 



A large genus of rose-red or crimson, filiform, articulated Algre of a delicately 

 membranaceous or sub-gelatinous substance, soon decomposing in fresh water. The 

 frond consists of a single series of large, elongated cells, Avith very transparent 

 walls, forming a broad limbus to the brilliantly coloured bag of endochrome con- 

 tained within. The branching is on a dichotomous model, occasionally varied by 

 the production of lateral branches, or converted partially into a trichotomous type. 

 The species are dispersed through the Northern and Southern Hemispheres. I can 

 claim only the following as yet for the North American Flora. 



G G 



