Hexacanth embryo

Gemmell, M.A. (1962) Natural and acquired immunity factors inhibiting penetration of some hexacanth embryos through the intestinal barrier. Nature 194, 701-702. 

Gemmell, M.A. (1964b) Species specificity of the immunogenic complexes of the tapeworm hexacanth embryo. Nature 204, 705-707. 

Gemmell, M.A. (1965) Immunological responses of the mammalian host against tapeworm infections III. Species specificity of hexacanth embryos in protecting sheep against Taenia ovis. Journal of Immunology 8, 281-290. 

Hatching of the cyclophyllidean egg involves two processes (a) the rupture of the egg shell (when present) and the passive digestion and/or disruption of the embryophore, (b) activation of the hexacanth embryo to become motile and rupture its enclosing oncospheral membrane. These processes frequently require different stimuli for their initiation. The hatching process has been reviewed by Lethbridge (442), and Ubelaker (888). 

Stage 7 Oncosphere formation. Characterised by the appearance, in the uterus, of embryonated eggs containing fully formed hexacanth embryos. 

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