along the margin, but destitute of lobes; in others the main frond is once 
or twice forked, one to two inches broad, and more or less furnished with 
lateral lanceolate segments, with the margin in every part jagged in a man- 
ner between dentate and ciliate, some of the cilia short and subulate, others 
more or less prolonged into lobes, which are themselves dentato-ciliate. 
Other specimens have the main frond somewhat palmately parted, the prin- 
cipal divisions from a quarter to half an inch wide, and closely pinnatifid 
with numerous patent laciniz, as wide as the main division, lanceolate and 
dentato-ciliate, acute, and much attenuated at base. The surface of the 
frond is either smooth or more or less muricated with cilia. Substance 
thick, rigid and erisp when recent, imperfectly adhering to paper m drying. 
Colour a deep, full red, semi-transparent when fresh, becoming much darker 
in the herbarium. The cells of the interior are oblong or narrow elliptical, 
in several rows, rather large and filled with large grains. Twubercles con- 
stantly lodged in the marginal cilia, near the apex, which is turned aside 
and projects like the bill of a bird. The sporular mass is beautifully 
arranged in moniliform strings, radiating from a central point; the termi- 
nal cells being at length formed into spores. etvaspores forming cloud-like 
stains in various parts of the frond, oblong, transversely zoned. 
Rhodymema ciliata is of a thicker substance, and more rigid 
than any other British species of this genus, and is, moreover, 
distinguished from all of them, except 2. jubata, by the fibrous 
character of the root. &. jubata, indeed, was long considered to 
be merely an extraordinary variety of A. ci/iata until characters 
were satisfactorily ascertamed by Mrs. Griffiths, which seem per- 
manently to separate it. These consist in a softer substance, a 
duller colour, and a difference in the fructification, and also in 
the season at which the plant is in perfection. It is only the 
smaller and narrower varieties of 2. ci/iata which can be con- 
founded with 2. jubata; the more usual form, which our plate 
represents, looks abundantly different. 
Fig. 1. RuopyMenta citiata. 2. A segment in fruit :—doth of the natural size. 
3. Fertile cilia, with tubercles. 4. Section of a tubercle. 5. Strings of 
spores, from the same. 6. Longitudinal section of the frond. 7, Trans- 
verse section. 8. Tetraspores :—all more or less magnified. 
