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A.N. Sial et al. / Gondwana Research 13 (2008) 437–452
451
Fig. 10. Organic-walled microfossils in palynological macerations of black
shales, lower La Silla Formation, Quebrada de La Angostura. (a–b) Sphaeroidal,
microgranular vesicles or colonies of probable bacterial affinity; (b–c) Cymatiogalea
Deunff (1961). (c) lower focus level, showing short processes at the
vesicle margin; (d) higher focus level showing characteristic polygonal fields;
(e) Large sphaeromorph, possibly Leiosphaeridia or Saharidia. All scale bars
represent 20 μm. Specimens illustrated are kept in the collection of the
Departamento de Geología, Facultad de Ciencias (Montevideo, Uruguay).
and a contribution to the IGCP project n. 478 (“Neoproterozoic-
Early Paleozoic Events in SW-Gondwana”).
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