title: Embryos and embryonic envelopes in eggs of two cyclophyllidean cestodes.
abstract: Membranes and envelopes around the embryos in eggs of Cotugnia digonopora and Raillietina (R.) echinobothrida have been studied in detail. This is the first study giving details of the egg-shell of a Cotugnia species. There are 3 membranes and an equal number of envelopes around the embryos in eggs of C. digonopora , while there are 2 membranes and only one envelope in case of eggs of R. echinobothrida . Noteworthy is the presence of a membrane in eggs of C. digonopora , termed "middle capsule", between and separating the 2 envelopes viz. the outer and inner. The membranes and envelope around the embryos in eggs of R. echinobothrida have been found to be identical with those of R. galeritae .--The 3 pairs of embryonic hooks of the 2 cyclophyllideans studied are collared --a feature of specific importance.
mesh_terms: D000818:Animals; D002589:Cestoda / Q000196:embryology*; D002645:Chickens / Q000469:parasitology*; D005260:Female; D007422:Intestines / Q000469:parasitology; D010063:Ovum / Q000648:ultrastructure; D013045:Species Specificity