( ISG ) 



adhering to the paper in drying. Colour, when young, a greenish ohve, 

 rusty brown when old. Fructification: consisting of oblong swellings 

 scattered among the upper ramuli, one or two near the middle or towards 

 the base of each ramulus, and containing a dark coloured mass. 



This is perhaps the most common, as well as the most abundant 

 species of the genus, forming large and beautifully silky masses, mostly 

 but not exclusively parasitical, in rock -pools, on the shelving shore, either 

 between tides or in deeper water. It is most frequent, perhaps, on Fucm 

 vesiculosm and serratus, but may be observed on all the larger, and even 

 occasionally on the smaller species of Alg£e, its fine brownish olive, or, 

 when past maturity, deep rusty brown, silky flagellse, forming a con- 

 spicuous object among every mass of sea-weed, either strewn on the 

 beach or in their native waters. 



It is one of the largest, and, although common, is one of the hand- 

 somest of the genus, at least when growing in its native pools ; its fine 

 silky fronds being so excessively divided, that the mass retains the water 

 like a sponge, or rather like a quantity of wool. 



Although very irregular in its ramification, it is veiy constant to that 

 irregularity, and the fructification, which is very rarely entirely wanting, 

 will at once serve to distinguish it from the other species of the genus, 

 with none of which is it likely to be confounded excepting the following, 

 and from that it can scarcely be distinguished excepting by its fruit. 



EXPLANATION OF PLATE CLXXIX. 



Fig. 1. — Ectocarpus litoralis, natural size. 

 2. — Branch. 

 3. — Fruit. Botli masnified. 



