ELECTRON MICROSCOPIC OBSERVATIONS ON SECOND-STAGE LARVAE OF POTATO ROOT EELWORM HETERODERA ROSTOCHIENSIS

Second-stage larvae of Heterodera rostochiensis were studied. The cuticle showed four layers. The striated fourth layer, which is also found in other nematodes, was given special attention. It is concluded that this layer consists of a geometric pattern of rods interconnected by membranes. A hypothesis concerning an antagonistic action of the cuticle with respect to muscle contraction is put forward. The forces exerted by the cuticle are thought to be able to work more efficiently than a turgor-pressure system in the production of undulating movements. Descriptions of the hypodermis, muscle cells, intestinal epithelial cells, and some other types of cells are also given. © 1968 Academic Press Inc.