| Name | Author | Source | Citation | Year |
|---|
| Acrochaetium gymnogongri | Setchell & N.L. Gardner in F.S. Collins, I. Holden, & W.A. Setchell | Phycoth. Bor.-Amer. | 45: no. 2244 | 1917 |
| Agardhiella coulteri | (Harvey) Setchell in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | 333 | 1897 |
| Alaria fistulosa f. platyphylla | Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | XLII | 1901 |
| Alaria fistulosa f. stenophylla | Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | XLIII | 1901 |
| Alaria praelonga f. nana | (H.F. Schrader) Setchell in Collins, Holden & Setchell | Phyc. Bor.-Amer. | 1292 | 1905 |
| Antithamnion floccosum var. pacificum | (Harvey) Collins, Holden, & Setchell | Phycoth. Bor.-Amer. | no. 147 | 1895 |
| Arthrospira jenneri f. purpurea | Collins in Collins, Holden & Setchell | Phycoth. Bor.-Amer.: | 1552 | 1909 |
| Avrainvillea nigricans f. fulva | M.A. Howe in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | no. 1480 | 1908 |
| Batrachospermum macrosporum | (H.C. Wood) F.S. Collins in Collins, Holden & Setchell | Phycoth. Bor.-Amer.: | no. 1087 | 1903 |
| Batrachospermum vagum f. tenuissimum_(`tenuissima') | Collins in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | no. 990 | 1902 |
| Bryopsis corticulans | Setchell in Collins, Holden, & Setchell | Phycoth. Bor.-Amer. | 13: no. 626 | 1899 |
| Bulbochaete nordstedtii f. suberecta | Collins in Collins, Holden & Setchell, | Phyc. Bor.-Amer. | 1681. | 1910 |
| Callithamnion byssoides var. jamaicense | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 443 | 1898 |
| Callithamnion halliae | F.S. Collins in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | no. 698 | 1900 |
| Callithamnion rupicola f. pygmaeum | Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1797 | 1911 |
| Callophyllis furcata | Farlow ex Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 883 (complete description on label) | 1901 |
| Callophyllis furcata f. dissecta | Farlow ex Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 883 | 1901 |
| Calothrix crustacea f. prolifera | (Flahault) N.L. Gardner & F.S. Collins in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | no. 1168 | 1904 |
| Calothrix crustacea f. simulans | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1406 | 1907 |
| Calothrix fasciculata f. incrustans | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 561 | 1899 |
| Ceramium strictum f. proliferum | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 847 | 1901 |
| Ceratothamnion pikeanum f. laxum | Setchell & N.L. Gardner in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | 943 | 1902 |
| Chaetomorpha californica | Collins in Collins, Holden & Setchell | Phyc. Bor.-Amer.: | 664 | 1900 |
| Chantransia virgatula f. tenuissima | Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | no. 741 | 1900 |
| Chondria dasyphylla f. floridana | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 996 | 1902 |
| Chondria tenuissima f. californica | Collins in Collins, Holden & Setchell | Phyc. Bor.-Amer.: | 636 | 1899 |
| Chroothece cryptarum | Farlow in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 752 | 1900 |
| Cladophora crispata f. subsimplex | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | no. 1193 | 1904 |
| Cladophora flexuosa f. floridana | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 978 | 1902 |
| Cladophora fracta f. reflexa | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | no. 1194 | 1904 |
| Cladophora gracilis f. elongata | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 725 | 1900 |
| Cladophora gracilis f. expansa | (Farlow) Collins in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | no. 981 | 1902 |
| Cladophora microcladioides f. stricta | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1583 | 1909 |
| Cladophora scopiformis ('scopaeformis') | (Ruprecht) Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | 922 | 1902 |
| Cladophora trichotoma f. elongata | Gardner in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 2141 | 1916 |
| Codiolum pusillum f. americanum | Foslie in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 869 | 1901 |
| Corallina crassa | (Lamouroux) Collins in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | 500 | 1898 |
| Corallina gracilis f. densa | F.S. Collins in Collins, Holden & Setchell | Phyc. Bor.-Amer.: | 650 | 1899 |
| Corallina granifera f. minor | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1450 | 1907 |
| Cordylecladia peaseae ('peasiae') | F.S. Collins in Collins, Holden, & Setchell | Proc. Amer. Acad. Arts & Sci. | 37: 255, no fig. | 1901 |
| Cystoclonium purpurascens f. stellatum | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1140 | 1903 |
| Dichothrix hosfordii | (Wolle) Bornet in Collins, Holden, & Setchell | Phycoth. Bor.-Amer. | no. 215 | 1896 |
| Ectocarpus confervoides f. brumalis | I. Holden in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 576 | 1899 |
| Ectocarpus confervoides f. irregularis | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 670 | 1900 |
| Ectocarpus fasciculatus f. polyrhizus | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1535 | 1908 |
| Egregia laevigata f. borealis | Setchell in Collins, Holden & Setchell | Phyc. Bor.-Amer.: | XL | 1901 |
| Enteromorpha flexuosa f. submarina | Collins & Hervey in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | no. 2161 | 1917 |
| Enteromorpha micrococca f. bullosa | Collins in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | no. 1067 | 1903 |
| Enteromorpha minima f. rivularis | Collins in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | Fasc. B, no. XXVI | 1901 |
| Eremosphaera viridis f. major | Moore ex Holden in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | no. 1315 | 1906 |
| Farlowia mollis | (Harvey & Bailey) Farlow & Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 898 | 1901 |
| Fauchea fryeana | Setchell in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | no. 1845 | 1912 |
| Fischerella thermalis var. americana | (Borzì ex Bornet & Flahault) Farlow in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | 211 | 1902 |
| Fucus platycarpus f. abbreviatus | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1339 | 1906 |
| Fucus vesiculosus f. gracillimus ('gracillima') | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 578 | 1899 |
| Fucus vesiculosus f. limicola | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1133 | 1907 |
| Gelidium crinale f. luxurians | F.S. Collins in Collins, Holden & Setchell | Phyc. Bor.-Amer.: | 1138 | 1903 |
| Gigartina canaliculata f. laxa | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1139 | 1903 |
| Gigartina papillata f. cristata | Setchell in Collins, Holden & Setchell | Phyc. Bor.-Amer. | 426 | 1898 |
| Gigartina papillata f. dissecta | Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 427 | 1898 |
| Gigartina spinosa var. pinnata | Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | CXXIII | 1911 |
| Goniotrichum humphreyi | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 421, incl. 8 figs. | 1898 |
| Gracilaria robusta | Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 635 | 1899 |
| Grateloupia cutleriae f. maxima | N.L. Gardner in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | CXXIV | 1911 |
| Grateloupia pinnata | (Postels & Ruprecht) Setchell in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | 947 | 1902 |
| Hecatonema maculans f. sauvageaui ('sauvageauii') | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1536 | 1908 |
| Hecatonema maculans f. solutum ('soluta') | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1038 | 1903 |
| Iridaea laminarioides f. minor | Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 587 | 1899 |
| Laminaria agardhii f. angustissima | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | LXXXIII | 1905 |
| Laminaria agardhii f. angustissima | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | LXXXIII | 1905 |
| Laminaria agardhii f. zostericola | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1084 | 1903 |
| Lyngbya subtilis | Holden in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | no. 1163 | 1904 |
| Merismopedia glauca f. mediterranea | (Nägeli) Collins in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | 1651 | 1910 |
| Nitophyllum violaceum f. crispulum | Setchell in Collins, Holden & Setchell | Phyc. Bor.-Amer.: | 694 | 1900 |
| Odonthalia dentata f. angusta | Harvey ex Macoun in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | no. 1297 | 1905 |
| Oscillatoria princeps f. purpurea | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 753 | 1900 |
| Oscillatoria salinarum | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1160 | 1904 |
| Pelvetia fastigiata f. limitata | Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1238 | 1905 |
| Pikea pinnata | Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 648 | 1899 |
| Pithophora varia | Wille in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 983 | 1902 |
| Porphyra perforata f. lanceolata | Hus in Collins, Holden & Setchell | Phycoth. Bor.-Amer.: | no. 683 | 1900 |
| Porphyra perforata f. segregata | Hus in Collins, Holden & Setchell | Phycoth. Bor.-Amer.: | no. 684 | 1900 |
| Prasiola gardneri | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1185 | 1904 |
| Pterosiphonia woodii f. pygmaea | Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | no. 1744 | 1911 |
| Ptilota pectinata f. tenuis | F.S. Collins in Collins, Holden, & Setchell | Phycoth. Bor.-Amer.: | 1148 | 1903 |
| Pylaiella gardneri | Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1384 | 1907 |
| Rhizoclonium tortuosum f. longiarticulatum | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | p. 1735 | 1911 |
| Rhizoclonium tortuosum f. polyrhiza | Holden in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 625 | 1899 |
| Rhodymenia palmata f. mollis | Setchell & N.L. Gardner in Collins, Holden & Setchell | Phyc. Bor.-Amer.: | 934 | 1902 |
| Rivularia compacta | F.S. Collins in Collins, Holden, & Setchell | Rhodora | 1: 10 | 1899 |
| Sarcophyllis californica f. pygmaea | Setchell in Collins, Holden & Setchell | Phyc. Bor.-Amer.: | 396 | 1897 |
| Sargassum bacciferum f. angustum | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 833 | 1901 |
| Sargassum vulgare f. ovatum | F.S. Collins in Collins, Holden, & Setchell | Proc. Amer. Acad. Arts & Sci. | 37: 248, no fig. | 1901 |
| Schizothrix simmonsiae | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 707 | 1900 |
| Scytonema junipericola | Farlow in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 756 | 1900 |
| Spirogyra orthospira f. purpurea | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1771 | 1911 |
| Spirogyra porticalis f. minor | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1263 | 1905 |
| Spongomorpha arcta f. limitanea | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | no. 1736 | 1911 |
| Stigeoclonium nanum f. subsimplex | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1375 | 1907 |
| Stilophora rhizodes f. contorta | Holden in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 679 | 1900 |
| Strepsithalia investiens | Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 738. | 1900 |
| Strepsithalia investiens | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 738 | 1900 |
| Tetraspora gelatinosa f. uniformis | F.S. Collins in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 1265 | 1905 |
| Ulva californica | J.N.F. Wille in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | 611 | 1899 |
| Ulva fasciata f. expansa | Setchell in Collins, Holden, & Setchell | Phyc. Bor.-Amer.: | LXXVII | 1905 |