308 Mr George Traill on the 



Order III— OOSPORES. 



Family. — VAXJ CHEPJ ACEtE. 



VATJCHERIA, De Candolle. 



37. Vaucheria sphserospora, Nordst. {Forma genuina, Nordst., and 



Forma dioica, Nordst. ) 



Kirkwall and Scapa Bays, in the shade on mud covered by the sea 

 at high tides only. July 1887 (G. W. T.). Certified by Proi 

 Nordstedt of Lund, Sweden. New to Orkney. 



Class. III.— P H^OPHYCE^. 



Order IV.— PH^OZOOSPORE^. 



Family.— SCYTOSIPHONACE^. 

 PHYLLITIS, Kutz. 



38. Phyllitis fascia (fZ. Dan.), Rke. [Laminaria fascia, Kg.) 



On rocks and stones in pools at about half-tide level Ahvays 

 submerged. Annual. March to November. Trichosporangia in 

 spring and summer. Rather rare. Found among other places at 

 Skaill, West Mainland. 



SCYTOSIPHON, Ag. 



39. Scytosiphon lomentarius (Lyngb.), J. Ag. {Chorda lomenta.ria, 



Lyngb.) 



Usually on rocks in pools between tide marks. Annual. March 

 to November. Nearly always submerged. Trichosporangia in July 

 and August. Large specimens in bays; smaller on exposed shores. 

 A minute form, about f inch high, occurs near high-water mark at 

 Kirkwall Bay, — corroborated by Kjellman. 



Family.— PUNCTARIACE^. 



LITOSIPHON, Haiv. 



40. Litosiphon Laminarise (Lyngb.), Harv. 



Epiphytic on Alar i a esculenta in pools near low-water mark. 

 Always submerged. Annual. June to October. Fruit in August. 

 Broch in Eousay, 1887 (G. W. T.). Found also at Skaill, West 

 Mainland, and at Kirkwall Bay. 



41. Litosiphon pusillus (Carm.), Harv. 



Epiphytic on Zodera iiKirina (M'Bain), also on Chorda filum. 

 Annual. Spores escape in July and August. Kirkwall Bay, good ; 

 Westness Bay, Rousay. 



