CERAMIUM. 165 



short, rosy ; dissepiments opake, swollen, purple. Substance tender and 

 flaccid. Colour of the tuft, pinky-purple. 



Section 3. CILIATA ; frond armed, at the dissepiments, with 

 one or more prickles, or bristle-like hairs. 



10. C. flabelligerum , J. Ag. ; frond subsetaceous, attenu- 

 ated upwards, rigid, flabellately branched, irregularly dicho- 

 tomous, with lateral, forked ramuli, the apices acute, patent 

 or somewhat incurved ; articulations coated with coloured 

 cellules, those of the lower branches about twice as long as 

 broad, of the upper equal in length and breadth, each armed 

 on the outer edge with a single, minute, subulate, coloured, 

 three-jointed prickle ; tetraspores erumpent, whorled round 

 the joint ; favellae 2 3 lobed, berry -like, subtended by seve- 

 ral, patent, subulate ramuli. Harv. Phyc. Brit. t. cxliv. 



On the smaller Algae, between tide-marks. Annual. Summer and au- 

 tumn. Rare. Torbay, Mrs. Griffiths; Jersey, Miss White; Blue Anchor 

 Bay, Miss Gifford ; Downshire 'Coast, Rev. W. Edwards. Frond 23 

 inches high, as thick as hogs' bristle, gradually attenuated, somewhat fla- 

 bellately branched. Articulations entirely covered with small cells. This 

 plant resembles a small variety of C. rubrum for which it may readily be 

 mistaken, if attention be not directed to the solitary thorn with which the 

 joints are armed. 



11. C. echionotum, J. Ag. ; frond slender, of nearly equal 

 diameter throughout, rigid, repeatedly dichotomous, fre- 

 quently with lateral forked branchlets, fastigiate, the apices 

 more or less involute ; articulations pellucid, those of the 

 middle of the stem three or four times longer than broad, the 

 upper gradually shorter, the uppermost extremely short ; 

 dissepiments coloured, armed with numerous, slender, irre- 

 gularly-inserted, subulate, colourless, one-jointed bristles ; 

 tetraspores mostly solitary in each joint, erumpent, along the 

 outer margin of the filament ; favellae mostly bi-lobed, late- 

 ral, subtended by numerous, strongly incurved ramuli. Harv. 

 Phyc. Brit. t. cxli. 



On rocks, stones, and the smaller Algae, between-tide-marks. Annual. 

 Summer and Autumn. Not uncommon. Forming very dense, fastigiate, 

 dark red or purple, somewhat rigid tufts. This species is at once recog- 

 nised by the numerous scattered and very slender bristles which clothe the 

 joints, so different from the whorled, robust prickles which distinguish Cer. 

 ciliatum. 



12. C. acatithonotum, Carm. ; frond slender, of nearly 

 equal diameter throughout, rigid, repeatedly dichotomous, 

 fastigiate, the apices strongly involute ; articulations pellu- 



