98 BRITISH MARINE ALG. 
obtuse at the tips, the frond throughout being marked at pretty regular 
intervals with distinct transverse lines, as indicated in the magnified 
branchiet in Fig. 91 (b). The colour of the living plant is a light pink, 
the stems inclining to pale yellow; but this species being of a rather 
gelatinous nature, decomposes quickly, and therefore no time should be 
lost in transferring it to paper. This liability to fade and decompose is 
even more characteristic of the species C. tenuissima, a rare summer annual 
which I have taken in perfection at Bovisand near Plymouth, and occa- 
sionally at Brighton. The growth and general appearance of this plant 
bear some resemblance to the foregoing, but it may be distinguished from 
that species at once, as wellas from Lawrencia obtusa (Fig. 89), which 
it also somewhat resembles, by its long slender ramuli, which are 
attenuated at both ends, many of them being tapered at the tips to a 
needle-like point. 
C. tenuissima is represented at Fig. 92, by a magnified branchlet, 
bearing several ovate ceramidia; the tetraspores are always produced 
throughout the whole length of the long bristle-like ramuli. The colours 
of this species have ail the fugitive characters of those of C. dasyphyjlla, 
though occasionally I have mounted young specimens, in which the 
lateral branches and ramuli were a deiicate purple, and the stems a fine 
primrose or chrome yellow. 
Tribe 2, has no British representative, but Tribe 3, contains three beau 
tiful genera, the first of which is represented on our shores and in brackish 
str ams by the curious species Bostrichia scorpioides (Fig. 93), both names 
being equally characteristic of the little curled or involute tips of the 
branches and some of the ramuli. I have taken this plant in the neigh- 
bourhood of Plymouth, but nowhere else. The fruit I have never seen, 
and I am not aware that it has ever been detected on British specimens. 
This species belongs to a group of very curious little plants, some of 
which are found in the tropics, others in the antarctic regions, and all are 
remarkable, according to Dr. Harvey, for their amphibious habits. A 
portion of one of my Plymouth specimens is represented at Fig. 93. 
The genus Rhodomela, signifying “‘ red and black,’’ (because the plants 
of this group, though a fine brown-red, turn black in drying), contains 
two British species. R. lycopodioides, is peculiarly a northern species, 
being found most abundantly on the shores of Scotland, on the north- 
east coast of England, and in the north of Ireland; on the English 
shores I have never taken this species further south than the rock 
pools above Tynemouth, where, in the spring, the beautiful red lateral 
branches of this plant are thrown out on each side of the stems 
throughout the whole frond. These tufted branches are so closely 
beset with multifid ramuli, that when they are mounted on paper they bear 
a fanciful resemblance to a wolf’s foot, whence the specific name. Fig. 94 
is from a long branch of this species. The capsules containing spores are 
produced on the tufted ramuli, tetraspores are immersed in the branchlets. 
R. subfusca is common on the southern shores. The summer and winter 
