The most remarkable feature of this cystic development is the formation in many genera of several internal buds within a common cyst, each of which forms an independent inverted scolex (Coenurus, Polycercus); or these internal vesicles may bud off a large number of scolices on their external surface (Staphylocystis).
On this view, therefore, at least two asexual generations (embryo and scolex) alternate with a sexual one (proglottides); and in the case of Staphylocystis the cyst contains two asexually produced generations, so that in such forms three stages (embryo, primary scolex-buds, secondary scolices) intervene between the proglottis of a Cestode and that of its offspring.
II.-A, a Coenurus from the brain of the sheep; the numerous scolices arise by invaginations of the bladder.
On this view, multiple scolices are, therefore, not buds, but an example of the unlocalized organization of the embryo such as occurs in other groups of animals, and is demonstrated by experiment.
II B) with many scolices; found in man, ungulates, carnivores, rodents and monkeys.