200 Rhodora [Ocronzn 
Lagerheim, |. c., p. 201, suggests that fresh water Chaetomorpha 
species should be expected in the United States, especially in Massa- 
chusetts, as the algal flora here has an almost tropical character. 
This characterization, which hardly seems to harmonize with the 
weather of the past winter and spring, was based on his inspection 
of desmids from ‘Tewksbury. ‘The occurrence of a fresh water C haeto- 
morpha, even farther north than Tewksbury, is of interest. 
Cladophora (Aegagropila) amphibia n. sp.  Filamentis inferioribus 
contortis; cellulis forma et magnitudine inaequalibus, subcylindricis, 
2—5 diam. longis, 40-70 » diam., aut 1-2 diam. longis, ad 100 # diam. 
in parte media incrassatis; filamentis abunde et irregulariter ramosis, 
ramis similibus, filamentis ramos erectos etiam gerentibus, 30—50 p 
diam., cellulis 4-8 diam. longis, subcylindricis at plus minusve irregu- 
laribus, paucos ramulos breves patentes emittentibus; cellula termi- 
nali obtusa vel truncata; rhizoidis incoloribus interdum a cellulis 
inferioribus ortis. 
Lower filaments contorted, cells of irregular form and size, subcylin- 
drical, 2-5 diam. long, 40-70 p» diam., or 1-2 diam. long, swollen to 
100 » diam. in the middle, freely and irregularly branched, branches 
of similar character; also bearing erect branches, 30-50 y diam., 
cells 4-8 diam. long, subcylindrical but somewhat irregular, bearing 
a few mostly short and patent branches; terminal cells obtuse or 
truncate; slender colorless rhizoids occasionally produced from the 
lower cells. On damp ground, among Salicornia, in a salt marsh, 
Alameda, California, Sept. 26, 1903, W. J. V. Osterhout & N. L. 
Gardner. Distributed as P. B.—A., No. 1284. 
This plant forms a thin extended layer on ground covered only at 
the highest tides, and has the habit of a Vaucheria. The lower part 
is densely matted, the upper surface is formed by the free ends of the 
erect branches. ‘These erect branches are fairly regular in form, 
varying from a true cylindrieal shape about as do the filaments of a 
Rhizoclonium; the basal filaments, however, are very irregular, the 
cells varying from long and cylindrical to short and ovoid, or of a 
triangular section, the latter apparently where a branch is starting 
from a short cell; cells of larger and smaller diameters may alternate, 
or there may be a series of swollen cells, giving a moniliform appear- 
ance. Some of the filaments end in a large, ovoid cell, others taper to 
a slender, tortuous rhizoid. In many cases the first cross wall in a 
branch is quite a distance from the base, reminding one of Siphono- 
cladus. ‘The cell wall is quite thick; the color is a dull green. Al- 
though observed by Dr. Gardner for a long time, no indication of 
Spores was seen. 
