THE connective-tissue sheath around the nervous system of insects began to attract attention after Hoyle (1953) had shown that it was essential for the normal functioning of the nervous system in Locusta migratoria. The sheath, which consists of two layers, the neural lamella and the sheath cells, controls the passage of ions from the haemolymph into the nervous system. In electron-microscope s...

Productive protrusions allowing motile cells to sense and migrate toward a chemotactic gradient of reactive oxygen species (ROS) require a tight control of the actin cytoskeleton. However, the mechanisms of how ROS affect cell protrusion and actin dynamics are not well elucidated yet. We show here that ROS induce the formation of a persistent protrusion. In migrating epithelial cells, protrusio...

The X(2) holder enables the effective production of thin, electron transparent samples for high-resolution transmission electron microscopy (HRTEM). Improvements to the X(2) holder for high-quality transmission electron microscopy (TEM) sample preparation are presented in this paper. We discuss the influence of backscattered electrons (BSE) from the sample holder in determining the lamella thic...

Annulate lamellae represent a poorly understood class of cytomembranes (see references 14-18). The structural resemblance and proximity (in some cases) between the nuclear envelope and annulate lamellae have led to the concept that the annulate lamellae represent a product of the nuclear envelope although the methods propoundedly involved in the morphogenesis of annulate lamellae are indeed var...

A new genus of Metopiinae, Ojuelos Khalaim, gen. n., with a single species, Ojuelos juachicus Khalaim & Ruíz-Cancino, sp. n., is described from Jalisco Province in central Mexico. Ojuelos belongs to the group of three genera (Cubus Townes & Townes, Colpotrochia Holmgren and Triclistus Förster) having a high lamella separating the antennal sockets and reaching the median ocellus (this lamella po...