Fig. 3

A Photomicrograph of the foot of Monacha obstructa showing side and sole of the foot are covered with epithelial layer (e), the inner connective tissue layer (ct), and glands embedded in the connective tissue (g). B, C Photomicrographs of the foot of Monacha obstructa showing B the foot sole is covered with simple columnar epithelium (co), and the connective tissue layer (ct) with many deeply embedded glands (g). C The side of the foot is covered with simple cuboidal epithelium (cu), and the connective tissue layer (ct) with few superficial glands (g). D, E Photomicrograph of the foot of Monacha obstructa exposed to UV-A for 3 h for two successive days showing D the sole of the foot with ruptured epithelial cells (r), deep folds (df), and undifferentiated epithelial cells (ue). E The foot sides with ruptured epithelial cells (re), deep folds (df), many empty glands (eg), the connective tissue layer (ct) with many empty spaces (s), and infiltrated hemocytes (h). F, G Photomicrograph of the foot of Monacha obstructa exposed to UV-A for 3 h for three successive days showing F the sole of the foot with ruptured connective tissue (rct) and ruptured epithelial layer (re). G The side of the foot with separated epithelial layer (se) disintegrated glands (dg)