180 ^ CENTURY OF PROGRESS IN THE NATURAL SCIENCES 



Family Hyellaceae Borzi (1914, p. 359) 



Syn.: Scopulonemataceae Ereegovic (1932, p. 138) 

 Family Dermocarpaceae Geitler (1925a, p. 247) 

 Family Clastidiaceae Drouet et Daily (1952, p. 223) 

 Family Chamaesiphonaceae Borzi (1882, p. 298) 

 Family Siphononemataceae Geitler (1925a, p. 251) 

 Family Endonemataceae Pascher (1929b, p. 347) 



Syn.: Pascherinemataceae Geitler (1942, p. 99) 

 Order HORMOGONALES (Thuret) Marchand orth. mut. Atkinson (1905, p. 163) 

 Syn.: Gloeosiphonales Wettstein (1924, p. 80); Oscillatoriales Copeland (1936, 

 p. 78); Nostocales Geitler (1925a, p. 252); Stigonematales Geitler (1925a, p. 

 252); Mastigocladales Elenkin (1938, p. 528); Diplonematales Elenkin (1938, 

 p. 535) 



Family Oscillatoriaceae (S. F. Gray) Dumortier ex Kirchner (1898, p. 61) 



Syn.: Borziaceae Borzi (1914, p. 358); Beggiatoaceae (Hansg.) Migula 



(1895, p. 41) ; Pseudonostocaceae Elenkin (1949, p. 1222) ; Schizo- 



thrichaceae Elenkin (1949, p. 1668) ; Crinaliaceae Elenkin (1949, p. 



1845); Vaginariacees (Gomont) Marchand (1895, p. 12); Lyngbyacees 



Kiitzing orth. mut. Marchand (1895, p. 12) 



Whether the Beggiatoaceae are colorless bluegreen algae or bacteria 



has been a matter of disagreement for a long time. The evidence in 



favor of placing them in the Schizophyceae is presented by Pringsheim 



(1949), 

 Family Gomontiellaceae Elenkin (1936, p. 543) 

 Family Nostocaceae Dumortier ex Engler (1892, p. 4) 



Syn.: Anabaenaceae Elenkin (1938, p. 643); Aphanizomenonaceae 



Elenkin (1938, p. 845) 

 Family Microchaetaceae Lemmermann (1907, p. 101) 



Syn.: Nodulariaceae Elenkin (1916, not seen, cited from Geitler, 1942, 



p. 159) ; Leptobasaceae Elenkin (1917, p. 164) 

 Family Rivulariaceae Kiitzing ex Bornet et Flahault (1886, p. 338) 



Syn.: Camptotrichaceae (West et West) Kirchner (1898, p. 90); Til- 



deniaceae Kossinskaja (1926, p. 82); Hammatoideaceae Elenkin (1949, 



p. 1806); Homoeothrichaceae Elenkin (1949, p. 1813);? Sokoloviaceae 



Elenkin (1926, pp. 93, 95; 1949, p. 1834; cf. Geitler, 1942, p. 176) 

 Family Scytonemataceae Kiitzing ex Bornet et Flahault (1887, p. 81) 



Syn.: Hydrocoryuaceae Elenkin (1949, p. 991); Plectonemataceae 



Elenkin (1949, p. 1772) ; Pseudoscytonemataceae Elenkin (1949, p. 



1805); Pseudodiplonemataceae Elenkin (1949, p. 1838) 

 Family Mastigocladaceae Geitler (1925a, p. 263) 



Syn.: Lithonemataceae Elenkin (1949, p. 185) 

 Family Diplonemataceae (Borzi) Elenkin (1934, p. 79) 



Syn.: Borzinemataceae Geitler (1942, p. 141) 

 Family Pulvinulariaceae Geitler (1925a, p. 254) 



Syn.: Loriellaceae Geitler (1925a, p. 253) 

 Family Capsosiraceae Geitler (1925a, p. 255) 



Syn.: Pseudocapsosiraceae Elenkin (1949, p. 1849) 

 Family Nostochopsidaceae Geitler (1925a, p. 257) 



Syn.: ?Loefgreniaceae Elenkin (1917, p. 161; cf. Geitler, 1942, p. 135) 

 Family Mastigocladopsidaceae Iyengar et Desikachary (1946, p. 58) 

 Family Stigonemataceae Kirchner (1898, p. 80) 



Syn.: Sirosiphonaceae (Stizenberger) Rabenhorst ex Engler (1892, 



p. 4) 



Phylum Rhodophycophyta 



Characterisation: The algae belonging to this phylum owe their characteristic red 

 color to the presence in their plastids of a water-soluble proteinaceous pigment (phycobi- 



