RHODOSPERMEA. 209 
and mount these delicate plants in sea-water, and to keep them from the 
light as much as possible until they are displayed and fixed on paper. 
The genus Seirospora is represented in Britain by one species only, the 
. beautiful Seirospora Grifithsiana (Fig.193). The generic name, signifying 
? 
** chain of seeds,’’ very aptly characterises the fruitful cells, which are 
produced in strings or chains, being in fact, transformations of the 
terminal joints of the ultimate ramuli of the tufted fastigiate branctes, 
as represented at Fig. 193; tetraspores, properly so-called, being also 
produced in strings, but scattered on various parts of the plant, and 
suspended on peduncles or short stalks. This charming species has all the 
appearance of a Callithamnion, and indeed Professor Agardh describes 
it under the name of Callithamnion seirospermum ; however, the general 
opinion of algologists seems to be in favour of Seirospora, and as such, 
I am content to letit remain. The fronds are tufted, and have each a 
main stem from 3in. to 6in. high, set on each side with numerous 
Fic. 194. Fruited branchlet 
niet Sere ae er of Corynospora pedicellata. 
alternate spreading branches; the lowest of these are longest, and are 
more or less furnished with secondary branches and ramuli, the tips of 
which generally incline upwards, and in these the strings of fertile cells 
are borne, the contents of which are of a brilliant crimson, the stems and 
branches being of a pale pink, and at maturity becoming fainter, and 
even inclining to a shade of yellow or pale straw colour. The whole 
plant is extremely flaccid and tender, but adheres to paper very readily, 
and forms a most attractive book specimen. It is very rare, though found 
on various parts of the British coasts. The finest specimens in my 
possession were taken at Plymouth, and recently a magnificent specimen 
was sent for my inspection by Mr. John Gatcombe, who gathered it there. 
The rare and beautiful alga now named Corynospora pedicellata (Fig.194), 
was, until recently, included in the Callithamnia, but the peculiarity of its 
tetrasporic fruit has led to its removal, and now it forms the only British 
