Plate XXXIX. 
Fig. 177. NITOPHYLLUM LACERATUM. 
Colour. Dull-purplish, or brownish-red. 
Substance. Membranaceous. Extremely thin ; cracking when dry. 
Character of Frond. A flat, rihless expansion ; unstalked {sessile) ; much slit and divided in 
a forked manner (dichotomously) The divisions (lacinice) sometimes narrow, like 
those of the narrow variety of N. punctatum (see Plate XXXYITI. Fig. 174, the 
upper form) ; sometimes as broad , as those of N. (Plate XXXYIII. Fig. 
176) ; generally obtuse ; margins either smooth and even or curled ; or fringed with 
small leafy frondlets. Distinctly marked veins rising from the base and spreading 
upwards. 
Measurement. From 2 to 10 inches long. 
Fructification. Of two kinds. 1. Clustered spores in globose scattered. 2. Tetra- 
spores in oblong groups (son) disposed along the margin, or in the fringing leaflets. 
Habitat. Our coasts generally. Near low-water mark. Common. 
The only Nitophyllum which reflects prismatic colours in the water. A variety has all the 
tips of the divisions turned in like hooks, and clings by them to the small alg£e near. For 
other Nitophyllums see Plate XL. Figs. 181 and 185. 
Fig. 178. PLOCAMIUM COCCINEUM. 
Colour. Bright pink-red ; particularly after a short exposure. 
Substance. Elastic, though thin ; not easily tearing. Giving out a pleasant scent in fresh 
water. 
Character of Frond. Flat, or nearly so ; very narrow ; tufted ; excessively branched. Main 
stems irregularly divided ; thickly set with alternate, spreading branches, which are 
furnished throughout with short-curved, pointed branchlets. Branchlets simple, or 
furnished on their inner face with a smaller set of short-curved, pointed branchlets, 
arranged four in succession ; these sometimes re-branchleted in a similar manner ; the 
compound branchlets resembling little combs. All the frond at one level as if cut 
out of paper. 
Measurement. From 2 to 12 inches long. 
Fmctification. Of two kinds ; external. 1. A mass of minute spores in globose capsules, un- 
stalked ; borne on the edge of the upper branches. 2. Tetraspores in minute, simple, 
or branched Stichidia ; on the branchlets. 
Habitat. Our coasts generally. On rocks and the larger algae, at low-water mark, or beyond. 
Common and abundant. 
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