56 
ULVACEiE. 
of the frond, to see the exact cellular structure, owing to the great transparency of the 
cell-walls, and the facility with which the endochromes are thrown out of their cavities 
when cross-sections are moistened. 
This is a very distinct species, remarkable for the great diameter of its worm- 
like filaments, and their clavate form. Notwithstanding its somewhat greater com- 
plexity of structure, I think there can he no doubt of its near affinity with B. fusco- 
purpurea. 
Plate XLIX. A. Fig. 1 . Bangia vermicularis , the natural size. Fig. 2. A frond mag- 
nified. Fig. 3. Base ; 4. middle portion ; and 5, apex of the same. Fig. 6 , 7, 8. Trans- 
verse sections at different heights. Fig. 9 and 10. Radiating endochrome-cells, all 
highly magnified. 
3. Bangia ciliaris , Carm. ; filaments very minute, (forming a rosy down on the 
fronds of other Algas) basifixed, straight ; granules either in a single series, or two or 
three in each transverse row. Harv. Phyc. Brit. tab. 322. Chauv. Rech. p. 37- 
Hab. Parasitic on Chondria atropurpurea , at Charleston, S. C., W.H.H. (v. v.) 
This forms a very short, bright, rose-red downy pile on the fronds of the Chondria. 
Each filament is scarcely the tenth of an inch in length, and consists either of a single 
row of cells shorter than their diameter ; or of a double or triple series of such cells. 
Possibly it may be only the very young state of B. fuscopurpurea ; but the habitat 
is different, and the colour much brighter. 
III. ENTEROMORPHA, Link. 
Frond tubular, membranaceous, green, reticulated. Fructification , granules, com- 
monly in fours, contained in the cells of the frond. 
The tubular frond distinguishes this genus from Ulva. The tube varies greatly in 
width, in different or even in the same species. Sometimes it is of no greater diameter 
than that of human hair ; and sometimes it is one or two inches across, forming an 
inflated bag. The species are widely dispersed, extremely variable in ramification and 
general appearance, and some of them are among the commonest of all littoral algse. 
The green stringlike weeds that infest the bottoms of boats and vessels lying in harbour 
are generally species of this genus, and mostly E. compressa , which is found in all parts 
of the ocean from the Arctic and Antarctic basins to the Equator. 
