A Synopsis of Plant Phyla 5 



Phylum I. MYXOPHYCEAE. The Shrne Algae. 



Single cells or threads of cells ; reproducing by fission and 

 gonidia; blue-green, brown-green, or fuliginous (with phycocy- 

 anin) ; cell walls usually soft and forming a gelatinous matrix by 

 fusion. Typically freshwater plants, often occurring in warm 

 and hot springs. 



Class I. ARCHIPLASTIDEAE. Nucleus without a mem- 

 brane, and not definitely outlined ; no definite chromatophores. 



Order Coccogonales. Plants unicellular or in colonies, com- 

 monly embedded in a gelatinous matrix, less often free floating. 



Family i. Chroococcaceae. Cells rounded, undifferentiated, in 

 a matrix, or free floating; propagation by fission, rarely by gon- 

 idia. ChroococciLS, Gloeocapsa, and Merismopcdia. (Pf. I, la, 

 50.) One genus, Sarcina, contains "bacteria." 



Family 2. Chamaesiphoniaceae. Cells more or less elongated, 

 differentiated into base and apex, epiphytic ; propagation by gon- 

 idia. Chauiacsiphon. (Pf. I, la, 57.) 



Order Hormogonales. Plants filamentous, simple or branched, 

 usually enclosed in a sheath. 



Family 3. Oscillatoriaceae, Cells in a single row, cyclindrical, 

 uniform, no heterocysts. Oscillatcria, Lyngbya, Microcoleus. 

 (Pf. I, la, 61.) Many genera, e.g. Beggiatoa, Bacillus, Vibrio, 

 etc., are colorless "bacteria.'' 



Family 4. Nostocaceae. Cells in a single row, moniliform, 

 heterocysts present. Nostoc, Anabaena, Cylindrospenmim. (Pf. 

 I, la, 70.) A few genera, e.g. Lenconostoc, Micrococcus, etc., 

 are "bacteria." 



Family 5. Scytonemataceae. Cells in a single row, cylin- 

 drical, heterocysts present. Scytoncma, Tolypothrix. (Pf. I, 

 la, 76.) 



Family 6. Rivulariaceae, Cells in a single row, tapering, het- 

 erocysts basal ; trichomes tapering from base to apex. Calothrix, 

 Rivularia. (Pf. I, la, 84.) 



Family 7. Camptotrichaceae. Cells in a single row, tapering, 

 no heterocysts ; trichomes tapering from the middle towards each 

 end. Camptothrix. (Pf. I, la, 90.) 



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