Margaritaceous: shining, like mother of pearl = nacreous; q.v.
Margin: that portion of a surface within the edge, bounded on the inner side by the sub-margin and consisting of a more or less dilated imaginary line.
Marginal: of, belonging to, or near the margin.
Marginal area: in Orthoptera; see mediastinal area.
Marginal bristles: in Diptera; are inserted on the posterior margin of the abdominal segment.
Marginal cell: in Diptera (Williston):= subcostal (Shiner):= radial (Comst.): in Hymenoptera:= radial and 2 (Comst.): in general that cell beyond the stigma.
Marginal field: in tegmina = costal field: q.v.
Marginal nervure or vein: in Orthoptera, = costa (Comst.): in Hymenoptera (Norton) = radius 3 (Comst.): in general, the vein forming the marginal cell.
Margined -ated: bounded by an elevated or attenuated margin: when the margin is edged by a flat border.
Marmorate -us: spots and lines irregularly disposed, as in marble: marbled. Mask: in the nymphs of Odonata, the modified labium which, when at rest, conceals the other mouth parts.