BOT.-VOL. I.] SAUNDERS— PHYCOLOGICAL MEMOIRS. I S3 



(occasionally 50-70// x 2o-30,a), most abundant on the upper side of the 

 ultimate branches but found also along the main stem and primary branches, 

 below apparently arising from the corticating filaments. 



Forming small, loose masses, 2 mm. to 5 or 6 cm. high, 

 on Desmarestia ligulata, Monterey; on Zostera leaves 

 with E. gramilosiis. San Pedro, California. 



16. Ectocarpus mitchellae Harv. 



Plate XXI, Figs, i and 2. 



Ectocarpus nntchellcE Harv., Ner. Bor.-Amer., I, 1851, 143- 

 Ectocarpus indicus Soxd., Zoll. Verz. Ind. Arch. ges. pflanz., 3, 1854. 



Plant arising from long, creeping filaments 10-15/7. wide; cells 5-10 times 

 as long as the diameter. Erect filaments unbranched below, bearing above 

 many alternate branches which have numerous short, spreading branchlets ; 

 branches and branchlets pointed or ending in a short hair ; main filament 

 25-40/^ wide, 1-3 times as long as the diameter ; chromatophores numerous, 

 smalli disk-form ; plurilocular sporangia cylindrical, obtuse, 50-100// x 18-35//, 

 sessile, mostly secund on the upper side of the branches. 



Forming light olive-green tufts 1-2 cm. high on rocks at 

 the low tide level. San Pedro, California. 



A careful study of the plant showed it to be identical with 

 the figures and description of E. indicus given by Askenasy 

 in Ein. Austr, Meersalg., 8, 1894. The same plant was 

 received from Prof. McClatchie named E. mitchellcB. 

 From a careful comparison of the plates and descriptions 

 of E. indicus and E. mitchellcE, the two species seem to 

 be identical. Mr. F. S. Collins has received the same 

 plant from San Diego, where it has been called E. viresccns 

 Thuret. He has "no doubt that Harvey's and Thuret's 

 species are the same." 



17. Ectocarpus siliculosus parvus, var. nov. 

 Plate XXII. 



Plants tufted, erect, 1-2 cm. high; primary branches numerous, alternate, 

 gradually contracted above into long hyaline hairs, bearing many short, 

 pointed branches. Cells with the main filament 21-30// broad, 1-3 times as 

 long slightly constricted at the joints; plurilocular sporangia narrowly lance- 

 olate or conical, 120-290// x 20-27//, pointed and often tipped with a long hair, 

 borne on a long or short stalk, abundant on the main filament and the 



