The Ultrastructure of the Intestinal Wall of Ancylostoma caninum

Abstract

Light and electron microscopic studies of the intestinal wall of the dog hookworm show the inner striated border is composed of individual rods, which possess the essential components of cilia, i.e. 9 peripheral shafts and 2 central ones and a basal corpuscle and granule. A layer of confluent homogeneous masses, interrupted by oval openings is separated from the striated border by a narrow layer beneath the cell membrane, traversed by the shafts of the rods. The principal or multinucleated cellular layer is divided into an inner granular portion, rich in mitochondria, and an outer homogeneous zone of densely packed endoplasmic reticulum. The prominent outer cell membrane appears structureless. Hitherto the existence of cilia in nematodes has been denied. The significance of their discovery in a nematode is discussed.