98 GUIDE TO LOCALITIES. 



istic, the rocks and stones being covered with large olive brown 

 rockweeds, or Fuci. At the upper tide-limit is the small F. di.i- 

 tichus growing in pools, followed lower down by immense masses of 

 F. vesicuIosHs and F. evanescens and at dead low tide by F. edentatus 

 with long, flat receptacles. Aacophyllum nodosum, the largest of 

 our Fuci, with massive, nodose bladders in the stems, is abundant 

 near low-water mark but is not in good fruit in August. Teachers 

 in search of Fucus in fruit should select F. i^esiodosus, the other 

 Fuci in fruit in this month not having separate male and female 

 conceplacles. In deep tide-pools at low water are to be found the 

 different kelps of which representatives of the groups of Lamiiiaria 

 saccharina and L. digitata are always to be found, and often with 

 them Alaria esculenta in which the fruit is borne in small basal 

 pinnae. During August the kelps are not seen at their best and 

 usually they do not fruit until autumn. The larger specimens of kelp 

 grow in deep water, but even in mid-summer one maj' find them 

 washed ashore in sheltered places in the rocks or on the beaches. 

 Laminaria lowjicrimn, with long hollow stipes and Agarum Tiir- 

 neri, well named the sea-colander from the numerous perforations 

 of the frond, are characteristic of our coast, although the latter 

 reaches perfection only in higher latitudes. The Fuci, as far as 

 the eye can see, form the mass of the littoral vegetation, but they 

 are covered with other epiphytic algse of which the two most com- 

 mon brown species are PifiaielJa Uttoralis and the shorter and 

 denser Elachista fucicola. In the tide-pools other filamentous 

 brown algae abound as well as Bcdfsia verrucosa which forms ir- 

 regular, warty crusts on the rocks. 



The Florideae, or red seaweeds, as a rule are more abundant 

 below low-water mark and, like the larger kelps, are to be sought 

 washed ashore in sheltered pools where they have been left by 

 the tide or on beaches. One cannot alwaj's count on finding the 

 more beautiful deep-water forms ; but one may expect at any 

 time Delesseria sinuosa, looking like a red oak leaf, the finely cut 

 Ptilota serrata, and Euthora cristata. Probably the best place in 

 the world for collecting the beautiful Euthora is the beach at Mag- 

 nolia after a storm. Certain red seaweeds will be found growing 

 in pools near low-water mark such as Cliondrus crispus, Irish moss, 

 which covers the rocks at dead low water and is collected for the 

 markets at Hingham and other places, and the digitate, membra- 

 nous Rhodymenia palmata, or dulse, which is sold to some extent 



