(30) 



I'amification, sometimes simple, to three or four times piunated ; 

 divisions either alternate or opposite, longest about the middle, all very 

 mx;ch attenuated at each extremity. The primary tendency of the 

 jjranches is to be distichous, but innovations are often prodviced on every 

 part of the stem and branches, so that in old plants the branching is 

 often rather iiTegular and crowded, and Dr. Harvey also notices some 

 varieties in which the stem is nearly naked, with a few very long, 

 virgate branches, much longer than the stem itself, which are clothed 

 with slightly compound ramuli, half an inch long ; and others in which 

 the whole plant is so densely crowded, and excessively compound, that 

 the plant becomes a matted ball, so dense that it becomes difficult to 

 trace its branching. Structure : central tube large, traversed by a few 

 very delicate inner cells, very large, oblong, becoming rounder and 

 smaller towards the circumference, where they are very minute. Sub- 

 stance gelatinous, very flaccid, soon decomj)osing in fresh water, and 

 closely adhering to paper. Colour, a fine transparent pink, often rather 

 pale, sometimes brownish, rather darker when dry. Ceramidia urceolate, 

 with a short mouth and flattened base, not uncommon, containing a 

 dense mass of very minute angiilar spores. Tetraspores triparted, 

 immersed in the ultimate ramuli, also common. 



This species is by no means uncommon on all jjarts of the coast, 

 seeming to prefer a flat shelving shore, with a hard stony bottom, where 

 it grows attached to stones, old shells, and even to other Algse. 



The genus Chrysymenia is distinguished from Chylocladia, with which 

 it was formerly associated, by the continuous central tube, and some 

 slight differences of habit. 



From Chylocladia kaliformis, with which it was confounded by the 

 earlier botanists, it may be readily known by the internal continuous 

 tube, and the external coiTCsponding constrictions so conspicuous in that 

 species, as well as by the very different form of the capsular fruit. Both 

 may be often found growing together, as they affect similar localities. 



Besides the varieties noticed in the description, we have one from the 

 Moray Frith, in which all the lower parts of the branches are naked ; 

 all the branch] ets being collected in dense fascicles at their summits, 

 giving the plant a very curious brush-like appearance. 



EXPLANATION OP PLATE LXXVL 



Fig. 1. — Chyclocladia clavellosa, natural size. 

 2. — Branch with capsule. 

 3. — Branch with tetraspores. 

 4. — Tetraspores. 



.5. — Longitudinal semi-section of stem. 

 6. — Cross section of seprment of same. All magnified. 



