"Anatomical Notes on Sutroa," Zoe. ii. 1892, p. 321.
"Pacific Coast Oligochaeta," Mem. California Acad. Sci. vol. ii.
Quart. J. Micr. Sci. xxxvi. 1894, p. 307.
See Spencer, Proc. Roy. Soc. Vict. v. 1893, and Fletcher, P. Linn. Soc. N.S.W. 1886-1888, for Australian forms; Rosa, Ann. Mus. civ. Genova, vi. 1886, x. 1890, and xii. 1892, for Oriental species, etc.
See Fletcher and Spencer, already quoted, for Australian species.