The mature proglottis of Calliobothrium eschrichti is 8-9 mm. long, whereas the strobila only measures 4-5 mm. in length. Species of Phylliobothrium, Anthobothrium, and Tetrarhynchus show a similar but not an equal contrast between the size of the parent and proglottis (P. J. van Beneden, "Les Vers Cestoides," Nouv. Mém. de l'Acad. Roy. d. Belgique, tom. xxv. 1850).
The difficult question of the nature of the Cestode body and Cestode larvae is adequately discussed by Braun, loc. cit. p. 1167.
Leuckart, Die Parasiten d. Menschen [English trans. by W. E. Hoyle]; Blanchard, Traité de Zoologie médicale, 1893.
For a full account of the history of this subject see Leuckart, Parasiten d. Menschen, p. 28; Braun, loc. cit. Bd. iv. p. 929 et seq.; Huxley, Collected Essays, vol. viii. p. 229.
By Grassi this form is considered identical with T. murina. The latter species is known, from this author's researches, to develop in rats without migration into an intermediate host. Should Grassi's synonymy prove correct, the presence of large numbers of this tape-worm in man would readily receive its explanation.