Stabilization of egg-shell in Paraplerurus sauridae (Digenea: Hemiuridae)

Abstract
The newly formed egg-shell from eggs in the proximal part of the uterus of Paraplerurus sauridae is colourless and transparent, whereas the shell from eggs in the distal uterus is golden yellow in colour. Histochemical tests reveal the presence of phenol, protein and phenolase in the freshly formed egg-shell. The egg-shell from eggs in the distal uterus shows the property of sclerotin. Histochemical reactions, chromatography and spectrum analysis reveal the presence of a dityrosyl linkage in the egg-shell. The nature of the protein component in the egg-shell is discussed.