tepicensis, in all these species the cells of the epidermis are more
isodiametric, larger and homogeneous in shape and size, and of course they are inflated.
The callus was formed by
isodiametric cells organized in compact form and originating by the division of spongy and palisade parenquima.
Wall surface with
isodiametric, polygonal cells, 20-35 pm wide (mean 28 pm on the central part of the achene face), giving to the achene an apparent meshed pattern.
The mesophyll has uniform parenchyma constituted by
isodiametric cells that are variable in size, with the formation of small intercellular spaces.
These divisions resulted in the formation of small groups of cells exhibiting meristematic characteristics, such as
isodiametric, denselystained cells with a high nucleous-to-cell area ratio (Fig.
The cortex displays an exodermis with Casparian bands (Figures 18-19), followed by the cortical parenchyma consisting of
isodiametric cells.
The mesophyll of the leaf base is formed of
isodiametric parenchymatic cells that become collenchymatic at later stages (Fig.
Epidermis of YLG was unisseriate with
isodiametric and rectangular cells in transverse section, turning into papilose ones and covered with a slightly more thickened cuticle at the ostiolar region (Fig.
The cells from the meristematic layers, which will form the photosynthetic tissue, are
isodiametric and show dense contents (Figure 2a-c).
We recognize three predominant patterns of venation common in fruit wings: 1) "simple subparaIlel," dominated by veins of a single order, occasionally dichotomizing and anatomizing with or without cross veins, usually delimiting elongate areoles, sometimes with an extremely fine intervening reticulum of
isodiametric areoles; 2) "fusiform-reticulate, subparallel" with a single order of very fine veins that regularly dichotomize and anatamose to form a uniform network of fusiform areoles, and 3) "complex reticulate," with veins forming reticulum of multiple vein orders, with the main veins giving rise to successively finer veins, commonly with arches and with more or less
isodiametric quadrangular to polygonal areoles, occasionally with freely ending veinlets.
Epiphylls and hypophylls differ in their adult epidermal patterns: epiphylls have larger cells, nearly
isodiametric, sinuous to sinuous-angulose walls, with stellate appearance, whereas hypophylls have cells 2-3 times longer than wide, with irregular undulations, shallow and deep, angulose or curve (Fig.