[67]

See von Graffs Monographie, pl. ix.; and Jensen, Turbellaria ad Litora Norvegiae, Bergen, 1878, pl. iv.

[68]

For the reproductive organs of Rhabdocoelida, consult von Graff, Monographie, "Die Acoela"; and Böhmig, Zeitschr. f. wiss. Zool. Bd. li. 1891, p. 167.

[69]

Untersuchungen ü. Platyhelminthen, Giessen, 1873, p. 101.

[70]

Compare the remarks on Trematodes, pp. [4-5].

[71]

Haswell, Monograph of the Temnocephaleae. Macleay Memorial Volume. Mem. iii. 1893.