Denkschr. Akad. Wiss. Wien, 1875 and 1877.
Arch. Zool. Expér. iii. 1874, and vi. 1877; Mém. Instit. Paris, xlv. 1892.
Vid. Medd. Nat. For. Copenhagen, 1880, 1882, 1884, etc.
Nat. Tijdschr. Ned.-Indie, 1885, etc.
Journ. Linn. Soc. Zool. xv. xxiii. and xxiv.; Cat. of Tunicata in Australian Museum, 1899; also Challenger Reports (see note 80).