Fig. 57. MESOGLOIA VIRESCENS. 
Colour. Olive-green ; often yellowish. 
Substance. Soft, gelatinous, slimy ; loose as if likely to tumble to pieces. 
Character of Frond. Cylindrical, slender, excessively branched. Branches long, spreading, on 
each side a stem ; irregularly alternate ; furnished with numbers of short branchlets. 
The whole frond looking hairy when examined ; partly from its loose structure ; 
partly from the colourless cobweb-like hairs with which it is clothed. 
Measurement. From 8 to 12 inches long. About the thickness of a crow’s quill. 
Fructification. Minute seeds {spores) concealed in the substance of the frond. 
Habitat. Our coasts generally. On rocks, stones, and algse, at half-tide level. Common. 
The structure of the Mesogloias is on the model of that of a hottle brush ; namely, a stalk 
surrounded with bristles. So the Mesogloias have a firm, internal stalk (axis), with radiating 
filaments surrounding it. These filaments, however, being delicate, and invested with gela- 
tine, the plants are all slimy-feeling to the touch. 
Fig. 58. CLADOSTEPHUS VERTICILLATUS. 
Colour. A dull green, inclined to olive ; darker and browner when old. 
Substance. Eigid ; harsh. 
Character of Frond. Bushy. Branches slender, cylindrical ; partly forked (dichotomous) ^ partly 
alternate or opposite, on each side a stem. Stems and branches frilled (whorled) at 
short intervals with short, incurved branchlets ; which siXQ jointed, that is, composed 
of cells joined together in a line. Many of these drop off during winter. 
Measurement. From 3 to 9 inches high. 
Fructification. Oval seeds (spores) borne on small branchlets which grow irregularly on the 
frond after the summer frills (whorls) die off. 
Habitat. Our coasts generally, except the north-east. On rocks and corallines. 
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