Marine Algae of the Cape Peninsula 63 



its mucilage has also a characteristic number of epiphytic or some- 

 times parasitic plants. Among the commonest are Suhria viliata, 

 Carpoblepharis flaccida, and Polysiphonia virgata. The first of 

 these has narrow bright red ribbon like fronds fringed with minute 

 reproductive bodies when fertile. This always frequents the base 

 of the stipes of Ecklonia, so that it is submerged in deep water. 

 When the stipes are cast up on the shore, these fronds quickly 

 bleach white, and are then gathered by the poor and eaten as a 

 vegetable. According to Mr. Tyson, this is the same plant as 

 is mentioned in the " Swiss Family Robinson " as being edible. 

 Other red Algae found at the base of Ecklonia stipes are 

 Epimen^a obiusa and Trematocarpus flabellatus. Higher up the 

 stipes are found the ragged looking Carpoblepharis flaccida and 

 Polvsiphonia virgata. Of these, Suhria vittata and probably also 

 Pol^siphonia virgata Fend rhizoids into the substance of the host 

 plant and may therefore be regarded as probably parasitic. 



Much more might be said about the distribution of the Algae on 

 these shores. One thing which has never received attention from 

 workers in this country is the comparison of the flora of the East 

 coast with its warmer seas with that of the west with its much 

 coldei water. Provisionally one may say that there is a predomi- 

 nance of the larger more leathery forms on the cold side ; Ecklonia, 

 Macrocystis, and Laminaria pallida are found on the west and 

 hardly at all on the east coast. On the other hand it is easy to 

 find plants which are characteristic of the warmer water, such are 

 Plocamium corallorhiza, Caulerpa ligulata, Dict})ota, and several 

 species of Ectocarpm, whilst a large number can tolerate both 

 habitats. That this difference is primarily due to the temperature 

 seems to be shown from the fact that on both the east and west 

 coast similar substrata may be found. Sandstone is characteristic 

 of much of False Bay, but at Simon's Bay and Oatlands 

 there is an outcrop of granite. Granite is characteristic 

 of the west coast, but at Kommetje there is a sandstone formation, 

 very similar in disposition to the granite boulders of certain coves 

 near Camps Bay. On the whole, a comparison of these places 

 gives the impression that sandstone offers the better substratum as 



