294 Mr George Traill on the 



POLYSIPHONIA, Grev. 



133. Polysiphonia atro-rubescens (Dillw. ), Grev. 



On sand-covered rocks, also in pools, near low-water mark, and 

 at a greater depth. All the year. Fruit in summer and autumn. 



134. Polysiphonia Brodisei (Dillw. ), Grev. 



On rocks, and sometimes epiphytic on Choi'daria JIagelUformis, 

 in pools generally near low-water mark. Annual. May to 

 September. Fruit in July and August. Not uncommon, amongst 

 other places, in rocks pools a little to the west of the ladies' bathing 

 pool, west of Dunbar. 



135. Polysiphonia byssoides (Good, and Woodw.), Grev. 



On rocks in deep water. Annual. June to October. Fruit in 

 July and August. 



136. Polysiphonia elongata (Huds.), Harv. 



On stones and shells in deep water. Earely growing between 

 tide marks. Perennial. Fruit in July and August. 



137. Polysiphonia fastigiata (Roth.), Grev. 



Usually epiphytic on Aacophyllum nodosum; rarely growing on 

 rocks as at the east of the esplanade. Always left uncovered by 

 the tide, and exposed to the light, for many hours daily. Perennial. 

 Fruit from June to September. 



138. Polysiphonia fibrata (Dillw.), Harv. 



On damp exposed rocks, and epiphytic on Algss, in the shade, a 

 little below half-tide level ; also in pools. Annual. Summer and 

 autumn. Fruit from June to September inclusive. Common. 

 Host plants : Gorallina officinalis, Polysiplionia nigrescens, Glado- 

 steplms spongiosus, Chondrus crispus, Laurencia piniiatifida, &c. 



139. Polysiphonia fibrillosa (Dillw.), Grev. 



On rocks, also epiphytic on Cladosteplms spongiosus, in clear 

 sunny pools from about half-tide level to near low-water mark. 

 Perennial. Fruit in July, August, and September. 



140. Polysiphonia formosa, Suhr. 



In pools between tide marks. Annual. May to September. 

 Fruit in August. This plant has generally been referred to P. 

 formosa, but it is not quite typical. 



141. Polysiphonia nigrescens (Huds.), Harv. 



Common on rocks in pools between tide marks ; also epiphytic on 

 Corallina officinalis. Perennial ; but more usual , duration from 

 March to October. Young fronds on old plants generally appear 

 in January. Fruit from June to September. 



142. Polysiphonia parasitica (Huds. ), Grev. 



On rocks in shaded pools between tide marks, and at a lower 

 level; also epiphytic on Laminaria hyperborea. Always sub- 



