(1) Between the laminæ of the cuticle of the mother cyst from small, detached portions of the parenchymatous layer; during their growth they bulge inwardly or outwardly and may separate themselves entirely from their parent cyst. In the latter case they lie between the mother cyst and the capsule of connective tissue formed by the host (E. granulosus or E. hydatidosus exogenus); when growing inwardly they reach the interior of the mother cyst (E. hydatidosus endogenus). Their number is very variable and does not depend on the size of the mother cyst. They are as big as, or bigger than, gooseberries.
Fig. 254.—A piece of the wall of an Echinococcus veterinorum stretched out and seen from the internal surface. A few brood capsules (the outline of which is only faintly shown), with scolices directed towards their interior and exterior. 50/1.
(2) According to some authors, endogenous daughter cysts arise also from a metamorphosis of scolices that have separated off from the brood capsule. This takes place in the following way: Fluid accumulates in the interior of the scolex, so that eventually nothing remains except a sac consisting of cuticle lined by parenchyma. The cuticle gradually thickens and several layers form (fig. 257).
Fig. 255.—Echinococcus hominis in the liver. The fibrous capsule and the wall of the echinococcus have been incised, so that the endogenous daughter cysts may be seen. Reduced. (After Ostertag, from Thoma.)
