30 
SIPHONACEiE. 
often elongate, spongy stipes, and a brushlike habit, not unlike that of a Penicillus ; 
and few algologists will question its claim to generic distinction. I am not quite sure 
that I do well in associating the following species in the same genus ; but I know not 
where else to place it, unless indeed in Vaucheria. The specimens, however, appear to 
be scarcely mature ; there is a resemblance in the colour and substance, and the habitat 
is not dissimilar ; and I am willing to think that more advanced specimens might 
exhibit more of the spongy stipe which forms the most tangible characterof this genus. 
The fruit has not been observed. 
1. Chlorodesmis ? V auchericeformis ; stipes obsolete; fronds subsessile, comoso 
penicillate, fastigiate, dark-green, composed of innumerable, slender, dichotomous, ex- 
ceedingly lubricous and subgelatinous, unicellular, cylindrical filaments ; apices equal, 
level-topped, obtuse. (Tab. XL. C.) 
Hab. On stones, at Brown’s Wharf, Key West, W.H.H. (v. v.) 
Stipes obsolete, consisting in a bulbous mass of interlaced, branching fibres, which 
throw up the erect and free filaments of which the frond is composed, These filaments 
form dense pencil-like tufts, about an inch high, and perfectly fastigiate. They are 
exceedingly slender, cylindrical, of equal diameter throughout, dichotomous, obtuse, 
gelatinoso-membranaceous, soft, and very lubricous, and filled with a dense, deep-green 
endochrome. Each filament is strictly unicellular, without articulation or constriction. 
Plate XL. C. Fig. 1 . Chlorodesmis V auchericeformis ; the natural size. Fig. 2. 
Portion of one of the branching unicellular filaments. Fig. 3 and 4, small portions of 
the same ; the latter figures magnified. 
VI. VAUCHERIA. D.C. 
Fronds densely caespitose, and somewhat interwoven ; each consisting of a single, 
irregularly branched, unicellular cylindrical filament. Cell-wall ve, ry thin and delicate. 
Endochrome granular. Sporangia lateral, on the sides of the branches. Antheridia 
cylindrical, hooked, accompanying the sporangia. 
The greater number of species of this genus occur in freshwater ponds, ditches, and 
streams, and probably several may yet be found in North America. I have received 
from Mr. H. W. Ravenel of South Carolina a specimen of a Vaucheria apparently 
allied to V. dichotoma , but not in a state to be recognised. It was found floating in 
limestone waters. Dried specimens of this genus are rarely of any use, as the specific 
character is generally lost in drying. 
