ULTRASTRUCTURE OF THE DUCTUS EPIDIDYMIDIS OF THE ECHIDNA, TACHYGLOSSUS-ACULEATUS

  • 1 January 1982
    • journal article
    • research article
    • Vol. 135  (OCT) , 625-634
Abstract
The ultrastructure of the ductus epididymidis of the echidna was examined and compared to the analgous cells in the ductus epididymidis of eutherian mammals. The ductus epididymidis is divided into only 2 segments which are homogeneous along their length. The initial segment in the echidna is structurally similar to the initial segment of the eididymis of other mammals which were studied, while the terminal segment is structurally different to the terminal segment of other mammals; it is involved in considerable apocrine secretion of membranous material. It is proposed that the evolution of the epididymis in therian mammals has involved the development of structurally distinct post-initial segments whch presumably are involved in post-testicular development and storage of spermatozoa.