Penetration glands in the onchospheres of Raillietina cesticillus

Abstract

1. (1) Onchospheres of Raillietina cesticillus stained with brilliant cresyl blue have been hatched in 0.135 M KCl, and the dynamic morphology of Reid's penetration glands during the hatching was demonstrated. 2. (2) The penetration glands of Raillietina cesticillus are U-shaped pouches. Each pair of secretory canals, which starts from two penetration glands, one on either side of the organism, opens to four secretory pores at the hook-bearing end of the onchosphere. 3. (3) The glandular secretion which is discharged from the four secretory pores is helpful in the process of penetrating the larval membranes. 4. (4) The glandular secretion shows a positive staining reaction with the PAS technique indicating that the glandular secretion contains polysaccharide complexes. 5. (5) The glandular secretion is spent while the onchosphere penetrates the digestive mucosa of the intermediate host and gets out into the hemocoel. The glandular secretion is, therefore, shown to play an active part in the penetration of the onchosphere into the digestive mucosa of the intermediate host.