Histochemistry of a cotylocercous cercaria: I. Glandular complex in Plagioporus lepomis

Abstract

Histochemical techniques were used to study the glandular contents of a cercaria tentatively identified as the larva of Plagioporus lepomis Dobrovolny. Results indicate that the mucoid glands are located dorsally and contain acid mucopolysaccharide, protein with elastin-like staining properties, and a sudanophilic substance. The contents of these glands are discharged prior to emergence from the snail to form a coat which covers the cuticle of the cercarial body. Protein with sulfhydryl groups was found in the cephalic glands. The caudal glands contain mucopolysaccharide, protein, calcium, and possibly other metal ions, and a sudanophilic material. Possible functions of these glands, with relation to their contents, are discussed.