A histochemical approach to the study of helminth morphology

Abstract

1. The egg-shell in many trematodes and pseudophyllidean cestodes is a quinone-tanned protein; and histochemical methods for polyphenol oxidase or for phenols may be used to demonstrate regions producing or containing shell material (i.e. the vitellaria, its ducts and the uterus) in whole mount preparations.2. Specimens so treated may be further stained by routine whole mount methods. Gower's carmine is particularly recommended.3. 70% alcohol was found to be the best general fixative for these methods.4. These histochemical methods—with certain modifications—may also be used for demonstrating the egg-shell producing regions in sections.5. Because of their affinity for basic proteins, bromo-phenol-blue and malachite green are suitable for staining these regions in sections. These stains are unsuitable for whole mounts.6. There is some evidence to suggest that all trematodes and pseudophyllidean cestodes do not form and harden their egg-shell by quinone tanning; consequently, some forms may give negative or unsatisfactory results with these methods.