Fig. 6

Bright-field TEM images of the epithelial cells of L. fortunei, showing coronal sections of a gill filament. In image (a), many frontal cilia [fc] are observed longitudinal to the gill filament, and in image (c) the fc are observed in cross-section. b, d Epithelial cells at higher magnification, displaying the nucleus [n], mitochondria [m], Golgi complex [g], vesicles [v], smooth reticulum [r], and glycogen granules [gg]. The region highlighted in image (c) shows possibly mucus in between the fc. The filled arrowheads in images (b, d) point out some vesicles, mitochondria, and glycogen granules. The open arrowheads in (b) indicate apparent non-junctional regions of the cell membranes with a slightly increased space. The outlined arrowheads in (d) indicate the septate junctions