[Cytological structures similar to those of steroid-producing glands in the mandibulary and Y glands of the crab Carcinus maenas L., whether normal or without eyestalk].

Mandibular glands and Y organs have characteristic organelles of steroid glands: a network of smooth endoplasmic reticulum and numerous mitochondria with tubular cristae. Development of S.E.R. and activation of mitochondria are stimulated in mandibular glands by eyestalk ablation.