References
- 1878 . Studies on the Hydroida . Ann. & Mag. Nat. Hist. ser. 5 , i April : 323 – 323 .
- 1878 . Protocolles de la Réunion du 14 Janvier , ix : 33 – 33 .
- Mereschkowsky , C. 1878 . Études sur les Éponges de la Mer Blanche . Mém. Acad. Sci. St. Pétersb. , xxvi ( 7 ) : 12 – 12 . 13
- It is probable that, in the two classes of the Sponges and the Hydromedusæ, the two layers are not yet entirely differentiated, although the experiments of Trembley with Hydra and the conversion of its entoderm into ectoderm have not been confirmed by the recent experiments of M. Engelmann (see Zoologischer Anzeiger 1878 4