Sev. Melanosi'Erme.e. Fam. Chordariea. 



Plate CCCXVIII. 



MESOGLOIA GRIFFITHSIANA, Grev. 



Gen. Char. Frond filiform, much branched, gelatinous ; the axis com- 

 posed of longitudinal, subsimple, interlacing fibres, invested with 

 gelatine ; the periphery formed of radiating, dichotomous, coloured 

 filaments. Fructification : ovate or elliptical, olivaceous spores, at- 

 tached to the filaments of the periphery. Mesogloia (Ag.), — from 

 fxeaos, the middle, and yXows, viscid-, from the gelatinous axis. 



Mesogloia Griffithsiana j frond slender, equal throughout ; branches 

 alternate or irregular, filiform, long, simple, nearly bare of ramuli. 



Mesogloia Griffithsiana, Grev. MS. Rook. Br. Fl. vol. ii. p. 387. Wyatt, 

 Alg. Danm. no. 48. Harv. Man. ed. 2. p. 47. Kiitz. Sp. Alg. p. 545. 



Hab. In rock-pools between tide-marks, rare. Annual. Summer. 

 Livermead, Torbay, Mrs. Griffiths. Sidmouth, Miss Cutler. Bound- 

 stone, Mr. MCalla. 



Geogr. Distr. Atlantic shores of Europe. 



Descr. Root a small disc. Fronds growing in tufts, filiform, about a line in 

 diameter, and from twelve to eighteen inches in length, with a percurrent, 

 undivided stem, set throughout with long, spreading, slender branches, 

 which are mostly simple and often naked, or having a very k\v spreading 

 or divaricating branchlets scattered at irregular intervals. When the plant 

 is in a growing state it is clothed with colourless, horizontal fibres, spread- 

 ing from every portion of the stem and branches, and making them look, 

 when seen under water, of much greater diameter than they really are. 

 In age the axis decays, and the branches become hollow. The filaments 

 of the periphery are closely set, club-shaped, and beautifully beaded. The 

 spores are obovate, and raised in short pedicels. Colour a rather pale 

 olive-green, becoming greener in fresh water. Suhstanve gelatinous, flaccid, 

 slippery. In drying, the frond shrinks considerably, and adheres closely 

 to paper. 



This species bears a striking resemblance in its ramification to 

 Chordaria flagellifornm> but is always of a much paler colour, 

 and the microscopic structure very different ; tin; axis being 

 much less dense, and the substance more gelatinous and tender. 

 Still there is a considerable similarity in structure, and evidentlj 

 an affinity, through this species, between the two genera. 



M. Griffithsiana worthily bears tin; name <>i' its discovi w 



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