DICTYOTACEiE. 57 



mates, and only one extending so far north as our south- 

 ern and western shores. 



Haliseris polypodioides. polypody-like Sea- 

 Endive. 



Fronds forked, entire at the edge, growing in tufts, from 

 six inches to a foot high, and having a peculiar pungent 

 smell. Fructification in a Hue of dots on each side of the 

 midrib. 



This is a rare and beautiful species, and one that can- 

 not be mistaken for any other. It grows in deep water, 

 or only just above extreme low-tide mark. It must, 

 therefore, be sought during the lowest spring tides which 

 occur at new or full moon. As it is prone to decay 

 rapidly, and to cause other weeds, with which it may be 

 in contact to do the same, it should be kept separate, 

 and laid down as quickly as possible. 



Genus XVI. PADINA. 



Root coated with woolly fibres. Frond ribless, leathery, 

 flat, fan shaped, marked with concentric lines, fringed with 

 jointed fibres, and rolled inwards at the top. Fructification 

 in lines running along the markings of the frond beneath the 

 epidermis. — The derivation of Padina has not been traced. 



Padina pavonia. Peacock's-tail Padina. 



The one species to which this genus is now restricted 

 is widely distributed in warm latitudes, and is especially 

 abundant in the Mediterranean. It grows in the deep- 

 er tide- pools, some distance above low- water mark, and 

 when seen in a luxuiiant state under water is beauti- 

 fully iridescent, and has very much the appearance of 

 miniature peacocks' tails. It is found in several loca- 



