48 YALONIACEiE. 



1. Blovgettia confervoides, ReiTv. (Tab. XLV. C.) 



Hab. At Key West, on rocks near low-water mark. Dr. Wurdeman, W. H. H. 

 Prof. Tuomey. (v. v.) 



Fronds filamentous, densely tufted ; the tufts spreading extensively, from an inch to 

 an inch and half in height, very dense, pulvinate and fastigiate. Filaments rigid, not 

 collapsing when removed from the water, about as thick as hog's bristle, sparingly 

 branched, decumbent at base, then ascending, and the tips erect. The main divisions 

 and primary branches are very patent, either arching backwards or quite recurved. 

 They are destitute of branches along their lower or outer side, and more or less furnished 

 with unilateral ramification on the upper ; generally with a long excurrent point desti- 

 tute of ramuli. Often the filament has but a single series of simple, secund ramuli ; 

 but in luxuriant specimens there is a second series of similar secund ramuli. Articula- 

 tions variable in length, dark coloured, with opaque dissepiments, and not collapsing 

 when dry, contracted at the nodes, three to six times as long as broad ; the terminal 

 cell always very much longer than the rest, and frequently 10-12 times as long as its 

 diameter. Apices very blunt. The articulations are filled with dense, viscid endochrome 

 full of large green granules, and frequently containing also prismatical crystals. The mem- 

 branous cell-wall is divisible into three or more separate membranes, one concentrically 

 placed within the other. The outer are hyaline without obvious structure ; but 

 the inner one is reticulated with very slender nervelike fibres, which run longitudinally 

 through the membrane parallel to each other, and are connected by oblique crossbars ; 

 so that the surface is divided into narrow, pointed areolae. The spores are seriated in 

 moniliform strings, four or more in each string, and attached to short free veinlets 

 which issue from the veins of the inner cell-wall. The colour when recent is a very 

 dark green ; when dry it becomes more olivaceous. The substance is very firm, and 

 the plant imperfectly adheres to paper in drying. 



Plate XLV. C. Fig. 1. Blodgettia confervoides ; the natural sjze. Fig. 2. Pecti- 

 nated branch. Fig. 3. Apex of the long terminal cell of the branch, the lower portion 

 represented with the outer cell-coats exfoliated. Fig. 4. Portion of the membrane of 

 the innermost cell-coat traversed by slender fibres, bearing strings oospores (?). Fig. 5. 

 One of the moniliform strings, apart. Fig. 6. Some of the crystals found in the cells. 

 All the latter figures more or less highly magnified. 



IV. ANADYOMENE, Lamour. 



Root fibrous. Frond stipitate, membranaceous, leaf-like, flabellately veined ; the 

 veins confervoid, radiating from the base to the margin, pedately multifid, excessively 

 branched, and everywhere closely anastomosing. Fructification unknown. 



