The Involvement of Cellular Elements other than Neoblasts in Dendrocoelum Lacteum Regeneration

In posterior stumps of Dendrocoelum lacteum, after amputation at a level of the body in which the regeneration of the head cannot take place, the testicular follicles remain almost unaffected. This result is similar to that obtained by us in Dugesia lugubris in which, after resection of the posterior ventral nerve cords, the testicular follicles, posterior to the wound, remained almost unaltered. In agreement with other workers' findings, the disappearance of the testes, after removal of the entire cephalic region, might indicate the involvement not only of neoblasts, but concurrently of spermatogonia, which are endowed with dedifferentiation capacity, in the regenerative phenomena.