290 RHODOPHYCEZ. 
times carried from one locality to another stones bearing individuals of 
this species, which continued to prosper in spite of the change of habita- 
tion, Isteeped many of them in lukewarm water, afterwards in boiling, 
and no part of the Batrachosperm appeared, under the microscope, 
to have undergone the slightest disorganization by these immersions, 
and certain sprigs, replaced in their native place, continued to vegetate 
after these experiments. I do not think that there exist other vegetables 
which boiling water does not immediately disorganize, there are not 
others that can resist temperatures so opposite.”— Bory. 
Plate CXXIIZ. Portion of filament X 200 diam. 
var. Boltoni. Cooke. 
This variety differs in the large size and very globose form 
of the joints of the whorls. The apices are very often setiform. 
Size. Cellules -025 x ‘02, or 022 x ‘018 mm. 
This variety, found by Mr Thomas Bolton, of Birmingham, seems to 
differ sufficiently to be worthy of notice as a distinct variety. In colour 
it was a beautiful green, with a tendency to pass into blue in drying. 
Plate CXXIV. Portions of a filamert X 200 diam. 
var, Stagnale. 4g. 
One or two inches long, blue or steel-blue. Whorls of the 
stem confluent, of the branches distant. 
Rabh. Alg. Eur. iii., 406. 
Batrachosperma ludibunda stagnalis, Bory. Ann. Mus. xx., 
» 42, 
. Batrachospermum stagnale, Hass. Alg. p 107. 
Conferva fontana nodosa, &c., Dill. Muse. f. 44, 
“This variety has great resemblance in form and diameter to con- 
fusum ; it is nevertheless shorter, but as thick. Its whorls are round 
and distinct ; they are more approximated the one to the other in the large 
stems, about which they are sometimes even confused. Their colour is 
a greenish-yellow, pale and livid.”—Hassall. 
var, alpestre. Shuttleworth. 
Frond black, very mucous, much branched, alternately form- 
ing very obtuse angles with the principal filaments. Whorls of 
the stem spherical, distinct, but approximate, branches com- 
pressed. 
Batrachospermum alpestre, Hass. Alg. 111, t. 14, f. 2. 
“ This species is easily recognized by the eye alone, either in its recent 
or dried state ; in the former its size, great lubricity, jetty black colour, 
and approximate, yet for the most part, exactly spherical whorls, are 
remarkable ; in the latter, in which also the black tint is preserved, it 
may be distinguished by the multiplicity of its branches, which are, 
except the primary ones, exceedingly short and irregular, and issue from 
the main filaments almost at right angles, and by their non-moniliform 
appearance. In drying, also, it shrinks considerably .”— Hassall. 
