【摘要】 本文记述了江苏北部下第三系一蓝藻化石新属弯线藻Camptonema,这是我国第三系蓝藻化石的首次报道,对苏北下第三系的划分、对比和沉积环境的研究,提供了新资料。更多还原

【Abstract】 Although rich palynological assemblages have been described from the Tertiarysediments of northern Kiangsu,our knowledge about the fossil algae of this regionremains very meagre.When macerating the bore samples recently collected from theDainan formation(Lower Tertiary)in Xinghua of northern Kiangsu,the writer foundsome filamentous blue-green algae which deserve special notice.The present papergives a brief description of a new form of Oseillatoriaceae,i.e.Camptonema sinensegen.et sp.nov.Division CyanophytaClass HormogoneaeOrder OscillatorialesFamily OscillatoriaceaeGenus Camptonema gen.nov.Type species:Camptonema sinense gen.et sp.nov.(Pls.Ⅰ,Ⅱ,figs.1—15)Diagnosis:Filament solitary,commonly bending or curling,earthworm-like inshape,1100μlong,9—20μwide.Trichomes multicellular,uniseriate,unbranched,notconstricted at joints.Cross wall distinct.Medial cells of trichome commonly disc-shaped,1.5—4.7μ long,7.2—21.1μ wide,1/5 to 1/6 as long as wide.Terminal cell dome-shaped.Sheath firm,yellow to brownish yellow in colour,2.3—11.7μ thick,commonlygradually constricted toward apices Reproduction apparently by hormogonia.Hor-mogonium short,equal to several cells of muture trichome in dimension.Helerocystsnot seen.更多还原