310 Mr George Traill on the 



50. Dictyosiphon hippuroides (Lyngl).), Kiitz. 



In pools at about half-tide level, and sometimes at a lower level. 

 Nearly always epiphytic on Chordaria jUKjelliformis. Annual. 

 May to November. Spores escape in July and August. Holland 

 Head, Inganess Bay ; Kirkwall Bay, growing in pools opposite 

 Iceland Skerry, 1887 (G. W. T). Mr Pollexfen has also several 

 fine specimens of this plant in his collection, recently identified 

 by Mr .Batters. Now for the first time recorded for Orkney. 



STICTYOSIPHON, Kutz. 



51. Stictyosiphon tortilis (Rupr.), Rke. 



Usually in pools at about half-tide level. Always submerged. 

 Annual. March to September. Fruit in July and August. Found 

 at Holm, East Mainland, by Mr J. W. Curs iter. Identified by 

 G. W. T. 1887. Corroborated by E. M. Holmes. New to Orkney. 



52. Stictyosiphon subarticulata (Aiescli.), Hauck. 



Lately identified by Mr Batters in Mr Pollexfen's collection. 

 Found at Skaill Bay, West Mainland. New to Orkney. 



53. Stictyosiphon brachiatus (£"«//. i?o<.), Bornet. {Ectoca'ijms brachiatus 



[Eng. Bot.), Ag.) 



Epiphytic on Rliodijmenia pahnata in pools between tide marks. 

 Always submerged. Annual. Fruit, June, July, August. East 

 side of Kirkwall Bay ; Eousay at Broch ; also at Skaill, West Main- 

 land ; and in the Loch of Stenness. Mr Pollexfen tells me that 

 his specimens from the locality last mentioned struck Harvey as 

 being "very curious," and as being more "rigid" than ordinary 

 specimens of Ectocarpus bracliiatu^. 



Family.— AETHKOCLADIACE^. 



ARTHROCLADIA, Duby. 



54. Ai'throcladia villosa (Huds.), Duby. 



Dredged in 5 or 6 fathoms (M'Bain). Annual. Summer and 

 autumn. Eare. Found once by Mr Pollexfen when dredging in 

 Kirkwall Bay near the mouth of the " String." 



Family.— SPOEOCHNACE^. 

 SPOROCHNUS, Ag. 



55. Sporochnus pedunculatus (Huds.), Ag. 



On rocks, shells, &c., in deep water. Annual. Summer and 

 autumn. Kirkwall Bay, clay bottom, 6 to 8 fathoms, fine ; Calf 

 Sound, coral ground, 8 to 15 fathoms, &e. 



STILOPHORA, J. Ag. 



56. Stilophora rhizodes (Ehr.), J. Ag. 



Growing on rocks, or epiphytic on Alga?, below low-water mark 

 in sheltered bays. Annual. Summer. 



