(44) 



ribless, obovate leaflets, flat and obtuse, gradually tapering into a short 

 cylindrical footstalk. The stem, slightly flattened and elliptical, is con- 

 tinued through the frond, which is thin, flat, linear-lanceolate, tapering 

 into the stem at the base, and at the summit into a long narrow point, 

 quite flat, or more or less crisped and folded, entire when young, but 

 soon becoming more or less split up into numerous lacinise. Structure 

 consisting of roundish or hexagonal cells, very minute towards the 

 circumference. Substance cartilaginous, closely adhering to paper, the 

 older parts often woody. Fructification consisting of obovate or pyriform 

 spores, closely packed into roundish spots or sori, vertically arranged 

 on the accessory leaflets. 



This fine species is abundant on all our northern shores, as well as on 

 those of Northern Europe, Asia, and North America, becomes rarer as 

 we proceed southwards, and appears to find its southern limit on the 

 coast of France. It forms a narrow belt immediately beyond low water, 

 preferring to be always covered, and is scarcely ever left bare by the 

 tide, unless at spring-tides, and then only partially. It may at times be 

 met with in shady pools, but such do not seem to be its favourite haunts, 

 being possibly too warm for its thriving well; indeed it does not object to 

 even the most exposed situations, often forming a dark brown fringe round 

 the steepest and most ex230sed headlands on the coast, generally forming- 

 dense continuous masses, seldom associating much with other Laminarioe. 



The accessory leaflets do not appear till the plants have reached a 

 length of several feet, and are said to be renewed as well as the frond 

 every yeai", the stem only being perennial, at the summit of which the 

 new growth commences. 



The membranous part of the frond is generally more or less waved 

 and crisped, but sometimes very much so, even in the young state, and 

 occasionally the crisping is all on the one side, in which case the frond is 

 curved round in the form of a ring. 



In several coast towns in Scotland it is frequently eaten by the people, 

 and often hawked through the adjoining country for sale; and although 

 no less abundant than the other edible species, generally sells at a 

 higher price, owing to the difficulty of procuring it at low water at 

 ordinary tides. The midribs, or occasionally the fruit-bearing leaflets, 

 are the parts which are eaten. 



EXPLANATION OF PLATE CXLVL 



Fig. 1. — Alaria esculenta, natuvMl size. 

 2. — Fructiferous leaflet. 

 3. — Section of same. 

 4. — Tetraspores. 

 5. — Sporules. All magnified. 



