Early Permian silicified floras from the Perdasdefogu Basin (SE Sardinia): comparison and bio-chronostratigraphic correlation with the floras of the Autun Basin (Massif central, France) Author Galtier, Jean Author Ronchi, Ausonio Author Broutin, Jean text Geodiversitas 2011 2011-03-31 33 1 43 69 http://dx.doi.org/10.5252/g2011n1a4 journal article 7722 10.5252/g2011n1a4 bf362508-4a23-4fb9-ad93-d75fe2d5cd7d 1638-9395 4596948 Cordaites cf. lingulatus Grand’Eury, 1877 ( Fig. 9F ) This leaf, found associated with the stem of Figure 9A , has a thin lamina ( 0.4 mm ), a smooth surface and very closely spaced veins (less than 0.4 mm interval, i.e. about 25 per cm). Rectangular sclerotic strands extend above and below veins; the mesophyll is differentiated into palisade and more or less spongy tissues. Despite similarities with the species C. lingulatus Grand’Eury as illustrated by Renault (1879) this leaf may represent variability of other species like Cordaites principalis Germar , as illustrated by Harms & Leisman (1961) .