Ser. RHODOSPERME®. Fam. Corallinee. 
Pirate CCCXLV. 
MELOBESIA POLYMORPHA, Zin. sp.) 
Grn. Cuar. Frond attached or free, either flattened, orbicular, sinuated or 
irregularly lobed, or cylindrical and branched (never articulated), 
coated with a calcareous deposit. Hructification : conical, sessile ce- 
ramidia, scattered over the surface of the frond, and containing a 
tuft of transversely parted, oblong ¢etraspores.—Named from one of 
the Sea-nymphs of Hesiod. 
Metoszsta polymorpha; frond attached to rocks, thick, stony, encrusting, 
or rising into short, clumsy branches, which are seldom much divided, 
and often merely rudimentary ; ceramidia minute, depressed, extremely 
numerous. 
Me Losesia polymorpha, Harv. Man. ed. 2. p. 108. 
MILLEPorRA polymorpha, Linn. Syst. Nat. 1285. Ellis and Soland. Zoop. 130. 
Nutireora polymorpha, Johnst. Brit. Lith. p. 238. t. 24. f. 1, 2, 3 (?), and 
t. 25. f. 23. (in part.) 
Sponeites polymorpha, Kitz. Sp. Alg. p. 699. 
CoRALLium cretaceum lichenoides, Hillis, Cor. p. 76. t. 27. fig. d. D. (fide fig.) 
Has. On littoral rocks all round the coast, extending beyond low-water 
mark, Common. 
Geogr. Distr. (Probably widely dispersed.) 
Descr. Frond at first appearing on the surface of rocks, pebbles, or shells, in the 
form of little stony pimples, which gradually become confluent, so as to form 
an uneven crust, resembling one of the crustaceous Lichens, and spreading 
over indefinite spaces. This crust gradually grows thicker by successive 
thin coats of cellular and calcareous substance formed and deposited on 
the surface, and is very irregular in form; sometimes continuing nearly flat, 
sometimes rising into irregular stony knobs or lumpy masses, and sometimes 
throwing up short, erect, scarcely divided branches. Ceramidia minute, 
dot-like, sunk deeply in the outer layer of cells, extremely numerous and 
often puncturing over the whole surface of fertile fronds as if they had been 
closely marked with pin-holes. Colour variable according to the locality, 
~ dark lurid purple near low-water mark, and passing into chalky-white as the 
specimens grow nearer high-water mark. Ced/s of which the frond is com- 
posed about twice as long as their diameter. Swdstance stony. 
eee 
To this form I refer most of the lumpy Wadhpores, with thick 
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