A Synopsis of Plant Phyla ii 



areolations, lines, or ribs; cells usually without spines, processes, 

 or hairs. "Long Diatoms," mostly in fresh waters. 



Family i6. Tabellariaceae. Rachis a narrow unmarked strip, 

 no slit; cells usually little shorter than broad, or longer; mostly 

 in filaments. Grainmatophora, Rhahdonema. (Pf. I, ib, loi.) 



Family 17. Meridionaceae. Rachis a narrow unmarked strip, 

 no slit; cells generally much shorter than broad; often in fila- 

 ments, cuneate in girdle view. Meridian. (Pf. I, ib, 107.) 



Family 18. Fragilariaceae. Rachis a narrow unmarked strip, 

 no slit; cells generally much shorter than broad; often in fila- 

 ments, generally rectangular in girdle view. Fragilaria, Synedra. 

 (Pf. I, lb, no.) 



Family 19. Naviculaceae. Rachis containing a median, elon- 

 gated slit. Navicular Amphipleura, Cymbella. (Pf. I, ib, 122.) 



Family 20. Bacillariaceae. Rachis containing a lateral elon- 

 gated slit (not plainly visible), Bacillaria. (Pf. I, ib, 142.) 



Family 21. Surirellaceae. Rachis a narrow unmarked strip; 

 valve with two lateral wing-keels each enclosing a slit. Surirclla, 

 Campylodiscus. (Pf. I, ib, 145.) 



Phylum IV. SIPHONOPHYCEAE. The Tube Algae. 



Plants coenocytic, filamentous, or saccate, often much branched, 

 and usually basally attached by rhizpids, from septate (consisting 

 of rows of coenocytes) to non-septate, the filaments single or ag- 

 gregated into a plant body of definite form; chromatophores dis- 

 coid or reticulated, parietal; propagation by (i) the internal di- 

 vision of the protoplasm of a part (sporangium), or of the whole 

 plant into spores, — in water into zoospores, — in the air into w^alled 

 spores; or by (2) the contraction of definite masses of protoplasm 

 into agamic resting-spores (aplanospores or chlamydospores) ; 

 generation by the union of (i) ciliated isogametes, (2) ciliated 

 heterogametes, or (3) spermatozoids with non-ciliated gynogam- 

 etes (eggs), or of (4) antherid nuclei (non-ciliated) with eggs, 

 in all cases producing zygotes. Typically freshwater and marine 

 algae (holophytes), from which many filamentous fungi (hys- 

 terophytes) have been derived. 



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