Fig. 233. CERAMIUM STRICTUM. 



Colour. Dark, livid purple, in deep water, paler and yellower in sunny situations. 



Substance. Membranaceous, but not very firmly adhering to paper. 



Character of Frond. Tufts of jointed threads {filaments) branched. Filaments as 



fine as human hair; of nearly the same tliickness throughout; irregularly 



forked; distantly branched below; more frequently and closely divided above; 



all the divisions upright and straight, with narrow sharp angles. The tips 



straight, or shghtly hooked inwards. 

 Joints. Colourless. Partition-lines {dissepiments), opaque, purple. 

 Measurement. From 2 to 4 inches long. 



Fructification. Of two kinds. 1. Minute spores in roundish capsules, sessile near the 

 tips of the branches; surrounded by several short slender branch letee^s 

 {ramelli) {involiicrated). 2. Tetraspores immersed in the partition-lines of 

 the joints. Very prominent. 



Habitat. South coast of England. South and west of Ireland. On corallines, &c. 

 in tide-pools near low-water mark. Not common. 



Fig. 234. CERAMIUM NODOSUM. 



Colour. A delicate red. 



Substance. Eigid; rather harsh to the touch when fresh. Imperfectly adhering to 

 paper. 



Character ofi' Frond. Tufts of jointed i\wQii({^ {fiUmients), excessively divided. Fil- 

 ametits as fine as human hair, or finer, of the same thickness throughout; 

 repeatedly and regularly forked, the angles of branching {axils) very wide. 

 The tips shghtly hooked. 



Joints. Colourless. Partition-lines {dissepiments), dark and swollen. 



Measurement. From 3 to 6 inches long. 



Fructification. Of two kinds. 1. Minute spores in globose capsules, sessile on the 

 tips of short special branchlets; with one or two minute, slender branch- 

 lets below. 2. Tetraspores, two or three together, borne on the outer edge 

 of short special branchlets. 



Habitat. On sandy shores, olten at the roots of Zoster a. Generally distributed. 



Fig. 235. CERAMIUM FASTIGIATUM. 



Colour. Pinky purple. 

 Substance. Solt and tender. 



Character of Frond, Tults of jointed threads {filaments) much branched. Fila- 

 onents very slender; hair-hke; of nearly the same thickness throughout; 

 regularly and repeatedly lurked from the base. The lower angles of branch- 

 ing {axils) distant, the upper very close; all narrow; the tips cut to one 

 level, forming a round outline; hooked inwards. 



Joints. Lower ones colourless; upper coloured. V^nlilioTi-lmQ^ {dissepiments) opaque; 

 swollen, purple. 



Measurement. Four or 5 inches long. 



Fructification. Only one kind observed. Minute spores in small round capsules 

 near the tips of the branchlets, with three or four very slender branchletm^s 

 below. 



Habitat. Our coasts generally. On rocks in tide-pools. liare. 



28 



