( 50 ) 



Description. — Root, a mass of branching fibres. Fronds filiform, 

 cylindrical, eight inches to two feet in length, one-half to one and a-half 

 inch in thickness, repeatedly divided, gradually attenuated upwards, and 

 slightly so to the base ; branches and stem. almost from the base every- 

 where beset with much and iiTegularly divided ramuli, apices acute. 

 Structm-e : axis about one-third the diametei*, consisting of delicate, 

 articulated longitudinal fibres, with joints three to foiir times as long as 

 broad, rather loosely placed ; around are aiTanged numerous — six to ten — 

 series of rather lai'ge, somewhat ovate, polygonal cells, smaller towards 

 the circumference and coloiu^ed, those at the surface very minute. Sub- 

 stance cartilaginous, soft, and more or less perfectly adhering to paper. 

 Colour, dull brownish purple, passing into yellowish brown in decay. 

 Tubercles spherical or oval, forming regular swellings in the smaller 

 ramuli, single, or two or three together, formed of the external cellular 

 stratum of the ramulus, and containing a mass of minute ovate spores, 

 produced by the metamorphosis of the cells of the axis (?). Tetraspores 

 oblong, roundish, quadi'izonate, produced from the coloured cells of the 

 surface of the ramuli ; both kinds of fruit common and abundant. 



This fine species is very common on all our shores, and often grows to 

 a large size, producing its fruit abundantly. The variety /3 is a singular 

 one, should it prove to be only a variety, and proves the close relation 

 between this and the true Ili/pnece, from which it has been separated by 

 Kiitzing. We have not met with this variety on the east coast, and 

 have not seen it in fruit. In specimens from the Isle of Wight the whole 

 plant is very slender and capillaceo-multifid, the branches but slightly 

 attenuated, sometimes thickened upwards, very patent or divaricating, 

 reciu'ved, twisted and interlacing, the ultimate ramuli often spiriform. 

 The structure is very much the same as in the normal form. In both 

 the axis is always more or less occupied by minute cells. In (3 the colour 

 is often a rather pale rusty brown. 



This is a very gi-aceful plant when well grown, and although its 

 colours are less gaudy than many of its neighbom^s, it generally forms a 

 conspicuous object in almost every rock-pool, where it generally grows in 

 single tufts, consisting of a number of individuals whose roots are all 

 matted together. 



EXPLANATION OF PLATE LXXXV. 



1. Cystoclonium ^nirjmrascens, natural size.— 2. Branclilet with tubercle.— 

 3. Section of tubercle. — 4. Spores. — 5. Transverse section of stem. — 6. Longi- 

 tudinal section of stem. — 7.Tetraspore. All magnified. 



